U.S. patent application number 12/320577 was filed with the patent office on 2009-08-06 for substrate processing apparatus and method for manufacturing semiconductor device.
This patent application is currently assigned to HITACHI KOKUSAI ELECTRIC INC.. Invention is credited to Tsutomu Kato, Masanori Sakai, Shinya Sasaki, Yuji Takebayashi, Hirohisa Yamazaki.
Application Number | 20090197424 12/320577 |
Document ID | / |
Family ID | 40932113 |
Filed Date | 2009-08-06 |
United States Patent
Application |
20090197424 |
Kind Code |
A1 |
Sakai; Masanori ; et
al. |
August 6, 2009 |
Substrate processing apparatus and method for manufacturing
semiconductor device
Abstract
A substrate processing apparatus according to the present
invention promotes supplying gases to spaces between adjacent
substrates without reducing the number of substrates which can be
collectively processed. The substrate processing apparatus
includes: a processing chamber for storing and processing
substrates stacked in multiple stages in horizontal posture; at
least one processing gas supply nozzle which extends running along
an inner wall of the processing chamber in the stacking direction
of the substrates and supplies a processing gas to the inside of
the processing chamber; a pair of inactive gas supply nozzles which
are provided so as to extend running along the inner wall of the
processing chamber in the stacking direction of the substrates and
so as to sandwich the processing gas supply nozzle from both sides
thereof along the circumferential direction of the substrates and
which supply the inactive gas to the inside of the processing
chamber; and an exhaust line for exhausting the inside of the
processing chamber.
Inventors: |
Sakai; Masanori;
(Takaoka-shi, JP) ; Takebayashi; Yuji;
(Toyama-shi, JP) ; Kato; Tsutomu; (Takaoka-shi,
JP) ; Sasaki; Shinya; (Toyama-shi, JP) ;
Yamazaki; Hirohisa; (Toyama-shi, JP) |
Correspondence
Address: |
OLIFF & BERRIDGE, PLC
P.O. BOX 320850
ALEXANDRIA
VA
22320-4850
US
|
Assignee: |
HITACHI KOKUSAI ELECTRIC
INC.
Tokyo
JP
|
Family ID: |
40932113 |
Appl. No.: |
12/320577 |
Filed: |
January 29, 2009 |
Current U.S.
Class: |
438/758 ;
118/663; 118/715; 257/E21.211 |
Current CPC
Class: |
C23C 16/45591 20130101;
C23C 16/405 20130101; C23C 16/4412 20130101; C23C 16/4584 20130101;
C23C 16/45546 20130101 |
Class at
Publication: |
438/758 ;
118/715; 118/663; 257/E21.211 |
International
Class: |
H01L 21/30 20060101
H01L021/30; C23C 16/54 20060101 C23C016/54 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 31, 2008 |
JP |
2008-020761 |
Nov 12, 2008 |
JP |
2008-290104 |
Dec 8, 2008 |
JP |
2008-312661 |
Claims
1. A substrate processing apparatus comprising: a processing
chamber for storing and processing substrates stacked in multiple
stages in horizontal posture; a processing gas supply unit for
supplying at least one type of processing gas to the inside of the
processing chamber; an inactive gas supply unit for supplying an
inactive gas to the inside of the processing chamber; and an
exhaust unit for exhausting an atmosphere of the inside of the
processing chamber, wherein the processing gas supply unit has at
least one processing gas supply nozzle which extends running along
an inner wall of the processing chamber in the stacking direction
of the substrates and which supplies the processing gas to the
inside of the processing chamber, and the inactive gas supply unit
has a pair of inactive gas supply nozzles which are provided so as
to extend running along the inner wall of the processing chamber in
the stacking direction of the substrates and so as to sandwich the
processing gas supply nozzle from both sides thereof along the
circumferential direction of the substrates, and which supply the
inactive gas to the inside of the processing chamber.
2. The substrate processing apparatus according to claim 1, further
comprising: a control section for controlling at least the
processing gas supply unit and the inactive gas supply unit,
wherein the control section controls the processing gas supply unit
and the inactive gas supply unit such that a supply flow quantity
of the inactive gas is greater than a supply flow quantity of the
processing gas.
3. The substrate processing apparatus according to claim 1, further
comprising: a heating unit for heating an atmosphere in the
processing chamber; and a control section for controlling at least
the heating unit; wherein the control section controls the heating
unit such that a temperature of the atmosphere in the processing
chamber becomes a certain processing temperature.
4. The substrate processing apparatus according to claim 3, wherein
a thermal decomposition temperature of the processing gas is lower
than the processing temperature.
5. The substrate processing apparatus according to claim 4, further
comprising: a control section for controlling at least the
processing gas supply unit and the inactive gas supply unit,
wherein the control section controls the processing gas supply unit
and the inactive gas supply unit such that a supply flow quantity
of the inactive gas is greater than a supply flow quantity of the
processing gas.
6. The substrate processing apparatus according to claim 1, further
comprising: a pair of straightening vanes outside of the inactive
gas nozzles, respectively, which are located on the inner side of
the processing chamber with respect to the inactive gas ejection
port.
7. The substrate processing apparatus according to claim 1, further
comprising: a pair of straightening vanes each of which extends
between the inactive gas supply nozzle and the substrate in the
vertical direction and located substantially parallel to the
orientation of the inactive gas ejection port.
8. A substrate processing apparatus comprising: an outer tube; an
inner tube which is installed inside the outer tube with at least
the lower end thereof being opened, and which stores the substrates
stacked in multiple stages in horizontal posture; a processing gas
supply unit for supplying at least one type of processing gas to
the inside of the inner tube; an inactive gas supply unit for
supplying an inactive gas to the inside of the inner tube; and an
exhaust hole provided at a position opposing the processing gas
supply nozzle on the side wall of the inner tube, wherein the
processing gas supply unit has at least one processing gas supply
nozzle which is vertically installed inside the inner tube so as to
extend in the stacking direction of the substrates and which has at
least one processing gas ejection port for supplying the processing
gas, and the inactive gas supply unit has a pair of inactive gas
supply nozzles which are provided so as to be vertically installed,
inside the inner tube, extending in the stacking direction of the
substrates and so as to sandwich the processing gas supply nozzle
from both sides thereof along the circumferential direction of the
substrates and which have at least one inactive gas ejection port
for supplying the inactive gas.
9. The substrate processing apparatus according to claim 8, wherein
a preliminary chamber is formed projecting outward in the radial
direction in the inner tube, the processing gas supply nozzle is
provided in the preliminary chamber, and the processing gas
ejection port is located outward in the radial direction with
respect to an inner peripheral surface of the inner tube.
10. The substrate processing apparatus according to claim 8,
wherein a first straight line connecting the processing gas supply
nozzle and the exhaust hole is configured to pass the vicinity of
the center of each substrate.
11. The substrate processing apparatus according to claim 10,
wherein the processing gas ejection port is configured to be opened
substantially parallel to the first straight line.
12. The substrate processing apparatus according to claim 10,
wherein second and third straight lines, connecting each of the
pair of the inactive gas supply nozzles and the exhaust hole,
respectively, are configured to sandwich the first straight line
from both sides thereof.
13. The substrate processing apparatus according to claim 12,
wherein the inactive gas ejection port is configured to be opened
substantially parallel to the second and third straight lines.
14. The substrate processing apparatus according to claim 12, the
inactive gas ejection port is configured to be opened in the
outward orientation with respect to the second and third straight
lines.
15. The substrate processing apparatus according to claim 8,
further comprising: a heating unit for heating an atmosphere in the
processing chamber; and a control section for controlling at least
the processing gas supply unit, wherein, the control section
controls the heating unit such that a temperature of the atmosphere
in the processing chamber becomes a certain processing
temperature.
16. The substrate processing apparatus according to claim 15,
wherein a thermal decomposition temperature of the processing gas
is lower than the processing temperature.
17. The substrate processing apparatus according to claim 8,
further comprising: a control section for controlling at least the
processing gas supply unit and the inactive gas supply unit,
wherein the control section controls the processing gas supply unit
and the inactive gas supply unit such that a supply flow quantity
of the inactive gas is greater than a supply flow quantity of the
processing gas.
18. The substrate processing apparatus according to claim 16,
wherein the control section controls the processing gas supply unit
and the inactive gas supply unit such that a supply flow quantity
of the inactive gas is greater than a supply flow quantity of the
processing gas.
19. A method for manufacturing a semiconductor device, comprising
the steps of: loading substrates stacked in multiple stages in
horizontal posture to the inside of a processing chamber;
processing the substrates, by supplying a processing gas, to the
inside of the processing chamber, from at least one processing gas
supply nozzle which extends running along an inner wall of the
processing chamber in the stacking direction of the substrates, and
by supplying an inactive gas, to the inside of the processing
chamber, from a pair of inactive gas supply nozzles which are
provided so as to extend running along the inner wall of the
processing chamber in the stacking direction of the substrates and
so as to sandwich the processing gas supply nozzle from both sides
thereof along the circumferential direction of the substrates; and
unloading the processed substrates from the processing chamber.
20. The method for manufacturing a semiconductor device according
to claim 19, wherein in the step of processing the substrates, a
flow quantity of the inactive gas supplied from each of the pair of
the inactive gas supply nozzles is set to be equal to or greater
than a flow quantity of the processing gas supplied from the
processing gas supply nozzle.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a substrate processing
apparatus having a step of processing a substrate and a method for
manufacturing a semiconductor device.
[0003] 2. Description of the Related Art
[0004] Conventionally, as one step of manufacturing processes for a
semiconductor device, for example, such as DRAM, a substrate
processing step for forming a thin film on a substrate has been
carried out. Such substrate processing step has been carried out by
a substrate processing apparatus which includes: a processing
chamber for storing and processing substrates stacked in multiple
stages in horizontal posture; a processing gas supply nozzle for
supplying a processing gas to the inside of the processing chamber;
and an exhaust line for exhausting the inside of the processing
chamber. Next, substrate processing step loads a substrate holder
which supports a plurality of substrates to the inside of the
processing chamber, and supplying the gas from the processing gas
supply nozzle to the inside of the processing chamber while
exhausting the inside of the processing chamber by means of the
exhaust line, whereby the gas is caused to pass spaces between each
of the substrates and thus a thin film is formed on each of the
substrates.
[0005] However, in the above-described substrate processing step,
the gas is difficult to flow to the vicinity of each of the
substrates. This causes difference in gas supply amount between to
the vicinity of the outer periphery and to the vicinity of the
center of each substrate, and accordingly the in-plane uniformity
of substrate processing sometimes deteriorates. For example, there
are some cases where a thin film formed in the vicinity of the
outer periphery of the substrate is thicker compared with a thin
film formed in the vicinity of the center of the substrate.
[0006] In order to promote supply of the gas to the vicinity of the
center of each substrate, a method can be conceived in which
ring-shaped straightening vanes are provided, each straightening
vane being between the circumferential edge of each substrate
supported by the substrate holder and the inner wall of the
processing chamber. However, in such a method, there are some cases
where a substrate transfer mechanism for transferring the
substrates to the substrate holder interferes (gets contact) with
the straightening vane. In the case where a large stacking pitch of
the substrates is given to avoid such interference, there are some
cases where the number of substrates which can be collectively
processed is reduced. In addition, the substrate holder which has
ring-shaped straightening vanes is easy to break and is expensive
because of complexity of the structure thereof.
[0007] As described above, in the above-described substrate
processing step, the gas is difficult to flow to the vicinity of
each substrate. This causes difference in gas supply amount between
to the vicinity of the outer periphery and to the vicinity of the
center of each substrate, and accordingly, the in-plane uniformity
of substrate processing sometimes deteriorates. For example, in the
case of an Hf oxide film (HfO film) formed by supplying an
amine-based Hf raw material gas and an O.sub.3 gas onto a
substrate, a Zr oxide film (ZrO film) formed by supplying an
amine-based Zr raw material gas and an O.sub.3 gas onto a
substrate, and the like, there are some cases where a film formed
in the vicinity of the outer periphery of the substrate is thinner
compared with a film formed in the vicinity of the center of the
substrate.
[0008] In order to promote supply of the gas to spaces between
adjacent substrates, a method can also be conceived in which
ring-shaped straightening vanes are provided, each straightening
vane being between the circumferential edge of each substrate
supported by the substrate holder and the inner wall of the
processing chamber. FIG. 4 is a schematic structural view of a
substrate holder which has such straightening vanes. By providing
ring-shaped straightening vanes such that they surround the
circumferential edge of the substrates, a part of the processing
gas can be adhered onto each straightening vane, whereby, a film
formed in the vicinity of the outer periphery of each substrate can
be made thinner. Note that, FIG. 5 is a schematic structural view
of a substrate holder which does not have straightening vanes.
[0009] However, in such a method, there are some cases where a
substrate transfer mechanism for carrying the substrates to the
substrate holder interferes (gets contact) with the straightening
vanes. In the case where a large stacking pitch of the substrates
is given to avoid such interference, there are some cases where the
number of substrates which can be collectively processed is
reduced, whereby productivity of the substrate processing
deteriorates. In addition, the substrate holder provided with
ring-shaped straightening vanes is easy to break and is expensive
because of complexity of the structure thereof.
[0010] Hence, the investors and the like made an intensive study on
a method of promoting supply of gases to the vicinity of the center
of each substrate without reducing the number of substrates which
can be collectively processed. As a result of this, the investors
have found the knowledge that supply of the gas to the vicinity of
the center of each substrate can be promoted and the supply amounts
of the gas to the vicinity of the outer periphery and to the
vicinity of the center of each substrate can be made more uniform,
by supplying an inactive gas from both sides of a processing gas at
the same time when supplying the processing gas to the inside of
the processing chamber. The present invention has been made on the
basis of such knowledge obtained by the investors and the like.
SUMMARY OF THE INVENTION
[0011] An object of the present invention is to provide a substrate
processing apparatus and a method for manufacturing a semiconductor
device which can promote supplying a gas to the vicinity of the
center of individual substrates without reducing the number of
substrates which can be collectively processed.
[0012] An aspect of the present invention is a substrate processing
apparatus: including a processing chamber for storing and
processing substrates stacked in multiple stages in horizontal
posture; a processing gas supply unit for supplying at least one
type of processing gas to the inside of the processing chamber; an
inactive gas supply unit for supplying an inactive gas to the
inside of the processing chamber; and an exhaust unit for
exhausting an atmosphere of the inside of the processing chamber.
In the substrate processing apparatus, the processing gas supply
unit has at least one processing gas supply nozzle which extends
running along an inner wall of the processing chamber in the
stacking direction of the substrates and which supplies the
processing gas to the inside of the processing chamber, and the
inactive gas supply unit has a pair of inactive gas supply nozzles
which are provided so as to extend running along the inner wall of
the processing chamber in the stacking direction of the substrates
and to sandwich the processing gas supply nozzle from both sides
thereof along the circumferential direction of the substrates, and
which supply the inactive gas to the inside of the processing
chamber.
[0013] Another aspect of the present invention is a substrate
processing apparatus: including an outer tube; an inner tube which
is installed inside the outer tube with at least the lower end
thereof being opened, and which stores the substrates stacked in
multiple stages in horizontal posture; a processing gas supply unit
for supplying at least one type of processing gas to the inside of
the inner tube; an inactive gas supply unit for supplying an
inactive gas to the inside of the inner tube; and an exhaust hole
provided at a position opposing the processing gas supply nozzle on
the side wall of the inner tube. In the substrate processing
apparatus, the processing gas supply unit has at least one
processing gas supply nozzle which is vertically installed inside
the inner tube so as to extend in the stacking direction of the
substrates and which has at least one processing gas ejection port
for supplying the processing gas, and the inactive gas supply unit
has a pair of inactive gas supply nozzles which are provided so as
to be vertically installed, inside the inner tube, extending in the
stacking direction of the substrates and so as to sandwich the
processing gas supply nozzle from both sides thereof along the
circumferential direction of the substrates and which have at least
one inactive gas ejection port for supplying the inactive gas.
[0014] A still another aspect of the present invention is a method
for manufacturing a semiconductor device including the steps of:
loading substrates stacked in multiple stages in horizontal posture
to the inside of the processing chamber;
[0015] processing the substrates, by supplying the processing gas,
to the inside of the processing chamber, from at least one
processing gas supply nozzle which extends running along an inner
wall of the processing chamber in the stacking direction of the
substrates, and by supplying an inactive gas, to the inside of the
processing chamber, from a pair of inactive gas supply nozzles
which are provided so as to extend running along the inner wall of
the processing chamber in the stacking direction of the substrates
and so as to sandwich the processing gas supply nozzle from both
sides thereof along the circumferential direction of the
substrates; and unloading the processed substrates from the
processing chamber.
[0016] According to a substrate processing apparatus and a method
for manufacturing a semiconductor device of the present invention,
it is possible to promote supplying a gas to the vicinity of the
center of each substrate without reducing the number of substrates
which can be collectively processed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a vertical sectional view of a processing furnace
of a substrate processing apparatus according to a first
embodiment;
[0018] FIG. 2 is a horizontal sectional view of a processing
furnace of a substrate processing apparatus according to a first
embodiment;
[0019] FIG. 3 is a schematic view showing flows of a processing gas
and an inactive gas inside the processing furnace;
[0020] FIG. 4 is a schematic structural view of a substrate holder
which has ring-shaped straightening vanes;
[0021] FIG. 5 is a schematic structural view of a substrate holder
which does not have straightening vanes;
[0022] FIG. 6 is a schematic structural view of a substrate
processing apparatus according to the first embodiment;
[0023] FIG. 7 is a table chart showing a result of substrate
processing in a comparative example;
[0024] FIG. 8 is a table chart showing a result of substrate
processing according to an example of the present invention;
[0025] FIG. 9 is a horizontal sectional view of a processing
furnace of a substrate processing apparatus according to a second
embodiment of the present invention;
[0026] FIG. 10 is a horizontal sectional view of a processing
furnace of a substrate processing apparatus according to a third
embodiment of the present invention;
[0027] FIG. 11 is a horizontal sectional view of a processing
furnace of a substrate processing apparatus according to a fourth
embodiment of the present invention; and
[0028] FIG. 12 is a horizontal sectional view of a processing
furnace of a substrate processing apparatus according to a fifth
embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The First Embodiment of the Present Invention
[0029] Hereinafter, the first embodiment of the present invention
will be described with reference to the drawings.
1. The Structure of the Substrate Processing Apparatus
[0030] First of all, an example of a structure of a substrate
processing apparatus 101 which executes a substrate processing step
as one of manufacturing processes for a semiconductor device will
be described. FIG. 6 is a perspective view of the substrate
processing apparatus 101 according to the present embodiment.
[0031] As shown in FIG. 6, the substrate processing apparatus 101
according to the present embodiment includes a housing 111. In
order to carry wafers (substrates) 10 made of silicon or the like
to and from the housing 111, a cassette 110 which serves as the
wafer carrier (substrate storage container) for storing a plurality
of the wafers 10 is used. A cassette stage (substrate storage
container delivery table) 114 is provided in the front inside of
the housing 111. The cassette 110 is placed on the cassette stage
114 by an unillustrated in-process carrier device, and is
configured to be unloaded from on the cassette stage 114 to the
outside of the housing 111.
[0032] The cassette 110 is placed on the cassette stage 114 by the
in-process carrier device such that the wafers 10 in the cassette
110 are in vertical postures and a wafer gateway of the cassette
110 faces upward. The cassette stage 114 is configured so as to 10
enable rotating the cassette 110 by 90.degree. in the longitudinal
direction to the rear side of the housing 111, causing the wafers
10 in the cassette 110 to be in horizontal posture, and causing the
wafer gateway of the cassette 110 to face the rear side of the
housing 111.
[0033] A cassette shelf (substrate storage container placement
shelf) 105 is installed at a substantially central portion in the
longitudinal direction inside the housing 111. The cassette shelf
105 is configured to keep a plurality of the cassettes 110 in
multiple stages and multiple rows. The cassette shelf 105 has a
transfer shelf 123 which stores the cassettes 110 to be carried by
a wafer transfer mechanism 125 which will be described later. In
addition, above the cassette stage 114, there is provided a spare
cassette shelf 107 which is configured to store the cassettes 110
preliminarily.
[0034] A cassette carrier device (substrate storage container
carrier device) 118 is provided between the cassette stage 114 and
the cassette shelf 105. The cassette carrier device 118 includes a
cassette elevator (substrate storage container elevating mechanism)
118a which can be raised and lowered while holding the cassettes
110, and a cassette carrier mechanism (substrate storage container
carrier mechanism) 118b, serving as the carrier mechanism, which
can move horizontally while holding the cassettes 110. The cassette
carrier device 118 is configured to carry the cassettes 110
alternately to and from the cassette stage 114, the cassette shelf
105, the spare cassette shelf 107, and the transfer shelf 123, by
the linkage operation of the cassette elevator 118a and the
cassette carrier mechanism 118b.
[0035] A wafer transfer mechanism (substrate transfer mechanism)
125 is provided to the rear of the cassette shelf 105. The wafer
transfer mechanism 125 includes a wafer transfer device (substrate
transfer device) 125a which can rotate or move straightly the
wafers 10 in the horizontal direction, and a wafer transfer device
elevator (substrate transfer device elevating mechanism) 125b which
raises and lowers the wafer transfer device 125a. Note that, the
wafer transfer device 125a includes tweezers (substrate transfer
fixture) 125c which holds the wafers 10 in horizontal posture. The
wafer transfer mechanism 125 is configured to pick up the wafers 10
from the inside of each cassette 110 on the transfer shelf 123 and
charge them onto a boat (substrate holder) 11 which will be
described later, and to discharge the wafers 10 from the boat 11
and house them in each cassette 110 on the transfer shelf 123, by
the linkage operation of the wafer transfer device 125a and the
wafer transfer device elevator 125b.
[0036] A processing furnace 202 is provided at the top rear section
of the housing 111. An opening is provided at the lower end section
of the processing furnace 202. Such opening is configured to be
opened and closed by a furnace opening shutter (furnace opening and
closing mechanism) 147. Note that, the structure of the processing
furnace 202 will be described later.
[0037] A boat elevator (substrate holder elevating mechanism) 115,
serving as the elevating mechanism, which raises and lowers the
boat 11 and carries it from and to the processing furnace 202 is
provided below the processing furnace 202. An arm 128, serving as
the connection device, is provided on the lifting table of the boat
elevator 115. A seal cap 9, serving as the cover body, is provided
on the arm 128 in horizontal posture. The seal cap 9 supports the
boat 11 vertically and closes the lower end of the processing
furnace 202 in air tight manner, when the boat 11 is raised by the
boat elevator 115.
[0038] The boat 11, including a plurality of holding members, is
configured to align, in the vertical direction, a plurality of (for
example, approx. 50 to 100) the wafers 10 in horizontal posture
with the centers thereof being matched with each other, and hold
them in multiple stages. The detailed structure of the boat 11 will
be described later.
[0039] A clean unit 134a including a supply fan and a dust-proof
filter is provided above the cassette shelf 105. The clean unit
134a is configured to circulate a clean air, which is a cleaned
atmosphere, to the inside of the housing 111.
[0040] Meanwhile, a clean unit (not shown), including a supply fan
and a dust-proof filter so as to supply a clean air, is installed
at the left end of the housing 111, which is the opposite side of
the wafer transfer device elevator 125b and the boat elevator 115
sides. It is configured such that the clean air blown out from the
unillustrated clean unit is circulated in the wafer transfer device
125a and the boat 11, and subsequently sucked in an unillustrated
exhaust device, and is exhausted to the outside of the housing
111.
2. The Operation of the Substrate Processing Apparatus
[0041] Next, the operation of the substrate processing apparatus
101 according to the present embodiment will be described.
[0042] First of all, the cassette 110 is placed on the cassette
stage 114 by unillustrated in-process carrier device such that the
wafer 10 is in vertical posture and the wafer gateway of the
cassette 110 faces upward. Subsequently, the cassette 110 is
rotated by the cassette stage 114 by 90.degree. in the longitudinal
direction to the rear side the housing 111. As a result of this,
the wafers 10 in the cassette 110 are in horizontal posture, and
the wafer gateway of the cassette 110 faces the rear side of the
housing 111.
[0043] Next, the cassette 110 is automatically carried to,
delivered to, and temporarily stored in to a specified shelf
position of the cassette shelf 105 or the spare cassette shelf 107
by the cassette carrier device 118, and subsequently transferred
from the cassette shelf 105 or the spare cassette shelf 107 to the
transfer shelf 123, or the cassette 110 is directly carried to the
transfer shelf 123.
[0044] When the cassette 110 is transferred to the transfer shelf
123, the wafer 10 is picked up via the wafer gateway from the
cassette 110 by the tweezers 125c of the wafer transfer device
125a, and charged into the boat 11 to the rear of a transfer
chamber 124 by the linkage operation between the wafer transfer
device 125a and the wafer transfer device elevator 125b. The wafer
transfer mechanism 125 which have delivered the wafer 10 to the
boat 11 returns to the cassette 110, and charges the subsequent
wafer 10 into the boat 11.
[0045] When a predetermined number of the wafers 10 are charged
into the boat 11, the opening at the lower end section of the
processing furnace 202 which has been closed by the furnace opening
shutter 147 is opened by the furnace opening shutter 147.
Subsequently, the seal cap 9 was raised by the boat elevator 115,
whereby the boat 11 holding the group of wafers 10 subject to
processing is loaded to the inside of the processing furnace 202.
After the loading, arbitrary processing is implemented to the
wafers 10 in the processing furnace 202. The processing will be
described later. After the processing, the wafers 10 and the
cassette 110 are released to the outside of the housing 111 in the
reverse sequence of the above-described sequence.
3. The Structure of the Processing Furnace
[0046] Subsequently, the structure of the processing furnace 202 of
the substrate processing apparatus according to the present
embodiment will be described. FIG. 1 is a vertical sectional view
of a processing furnace of a substrate processing apparatus
according to one embodiment of the present invention. FIG. 2 is a
horizontal sectional view of a processing furnace of a substrate
processing apparatus according to one embodiment of the present
invention. FIG. 3 is a schematic view showing flows of a processing
gas and an inactive gas inside the processing furnace. Note that,
the processing furnace 202 according to the present embodiment is
configured as the CVD device (batch-type vertical-shaped hot
wall-type vacuum CVD device) as shown in FIG. 1.
[0047] The Process Tube
[0048] The processing furnace 202 includes a vertical-shaped
process tube 1 which is arranged in the vertical direction such
that the center line thereof is vertical and is supported by the
housing 111 in a fixed manner. The process tube 1 includes an inner
tube 2 and an outer tube 3. The inner tube 2 and the outer tube 3,
made of a heat resistant material, such as quartz (SiO.sub.2),
silicon carbide (SiC), or the like, are integrally formed into
cylindrical shapes, respectively.
[0049] The inner tube 2 is formed into a cylindrical shape with the
upper end being closed and the lower end being opened. In the inner
tube 2, a processing chamber 4 is formed, which stores and
processes the wafers 10 stacked in multiple stages in horizontal
posture by the boat 11 as the substrate holder. The opening at the
lower end of the inner tube 2 constitutes a furnace opening 5
through which the boat 11 holding the group of wafers 10 is taken
in and out. Therefore, the inner diameter of the inner tube 2 is
set so as to be greater than the maximum outer diameter of the boat
11 holding the group of wafers 10. The outer tube 3, which is
similar to and slightly greater than the inner tube 2, is formed
into a cylindrical shape with the upper end being closed and the
lower end being opened, and covers the inner tube 2 concentrically
as if the outer tube 3 surrounds the outer side of the inner tube
2. Both lower end sections between the inner tube 2 and the outer
tube 3 are sealed by a manifold 6 formed into a circular-ring shape
in air tight manner. The manifold 6 is mounted on the inner tube 2
and the outer tube 3 detachably and attachably for the maintenance
operation and the cleaning operation for the inner tube 2 and the
outer tube 3. The manifold 6 is supported by the housing 111,
whereby the process tube 1 is in the state where it is installed
vertically.
[0050] The Exhaust Unit
[0051] An exhaust tube 7a, which serves as the exhaust line for
exhausting the atmosphere in the processing chamber 4, is connected
to a part of the side wall of the manifold 6. An exhaust port 7 for
exhausting the atmosphere in the processing chamber 4 is formed at
a connection section of the manifold 6 and the exhaust tube 7a. The
inside of the exhaust tube 7a is communicated, via the exhaust port
7, with an inside of an exhaust passage 8 which is constituted by
the clearance formed between the inner tube 2 and the outer tube 3.
Note that, the horizontal cross-sectional shape of the exhaust
passage 8 is a circular-ring shape with a constant width. A
pressure sensor 7d, an APC (Auto Pressure Controller) valve 7b
serving as the pressure regulating valve, a vacuum pump 7c serving
as the vacuum exhaust device, are provided in the exhaust tube 7a
in this order from the upstream thereof. The vacuum pump 7c is
configured to be capable of evacuation such that the pressure in
the processing chamber 4 becomes a certain pressure (degree of
vacuum). A pressure control section 236 is electrically connected
to the APC valve 7b and the pressure sensor 7d. The pressure
control section 236 is configured to control the opening of the APC
valve 7b on the basis of the pressure detected by the pressure
sensor 7d such that the pressure in the processing chamber 4
becomes a desired pressure at a desired timing. An exhaust unit
according to the present embodiment is constituted mainly by the
exhaust tube 7a, the exhaust port 7, the exhaust passage 8, the
pressure sensor 7d, the APC valve 7b, and the vacuum pump 7c.
[0052] The Substrate Holder
[0053] The manifold 6 is configured such that the seal cap 9, which
closes the lower end opening of the manifold 6 abuts against the
manifold 6 from the bottom in the vertical direction. The seal cap
9 is formed into a disk shape having an outer diameter which is
equal to or greater than the outer diameter of the outer tube 3.
The seal cap 9 is configured to be raised and lowered in the
vertical direction in horizontal posture by the boat elevator 115
which is vertically installed outside of the process tube 1.
[0054] The boat 11, which serves as the substrate holder for
holding the wafers 10, stands vertically on the seal cap 9 by being
supported thereby. The boat 11 includes a pair of upper and lower
end plates 12, 13, and a plurality of holding members 14 provided
vertically between the end plates 12, 13. The end plates 12, 13 and
the holding members 14 are made of a heat resistant material, for
example, quartz (SiO.sub.2), silicon carbide (SiC), or the like. At
each holding member 14, a plurality of holding groove 15 are
provided at equal intervals in the longitudinal direction. In each
holding member 14, the holding grooves 15 are provided so as to
oppose with each other. The circumferential edge of each wafer 10
is inserted into the holding grooves 15 in the same stage of the
plurality of holding members 14, whereby the boat 11 is configured
such that the plurality of wafers 10 are stacked and held in
multiple stages in horizontal posture with the centers thereof
being matched with each other.
[0055] In addition, a pair of upper and lower auxiliary end plates
16, 17 are provided by being supported by a plurality of auxiliary
holding members 18 between the boat 11 and the seal cap 9. At each
auxiliary holding member 18, a plurality of holding grooves 19 are
provided. Each holding groove 19 is configured such that a
plurality of disk-shaped insulating plates 216, made of a heat
resistant material, for example, quartz (SiO.sub.2), silicon
carbide (SiC), or the like, are charged in multiple stages in
horizontal posture. The insulating plates 216 is configured to make
it difficult to transmit heat of a heater unit 20, which will be
described later, to the manifold 6 side.
[0056] A rotating mechanism 254 for rotating the boat is provided
on the seal cap 9 at the opposite side of the processing chamber 4.
A rotation axis 255 of the rotating mechanism 254 passes through
the seal cap 9 and supports the boat 11 from the bottom. The
rotating mechanism 254 is configured to be capable of rotating the
wafers 10 in the processing chamber 4 by rotating the rotation axis
255. The seal cap 9 is configured to be raised and lowered in the
vertical direction by the above-described boat elevator 115,
whereby the boat 11 can be carried to and from the processing
chamber 4.
[0057] A drive control section 237 is electrically connected to the
rotating mechanism 254 and the boat elevator 115. The drive control
section 237 is configured to control the rotating mechanism 254 and
the boat elevator 115 such that they perform a desired operation at
a desired timing.
[0058] The Heater Unit
[0059] At the outside of the outer tube 3, the heater unit 20 is
provided such that it surrounds the outer tube 3. The heater unit,
as the heating mechanism for heating the inside of the process tube
1, heats the entire process tube 1 uniformly over or heats it so as
to have a certain temperature distribution. The heater unit 20, in
the state where it is vertically installed by being supported by
the housing 111 of the substrate processing apparatus 101, is
configured as the resistance heater, for example, a carbon heater,
or the like.
[0060] A temperature sensor, which is not shown, serving as the
temperature detector, is installed inside the process tube 1. A
temperature control section 238 is electrically connected to the
heater unit 20 and the temperature sensor. The temperature control
section 238 is configured to control the conductivity status to the
heater unit 20 on the basis of the temperature information detected
by the temperature sensor, such that the temperature in the
processing chamber 4 has a desired temperature distribution at a
desired timing.
[0061] A heating unit according to the present embodiment is
configured mainly by the heater unit 20, and the unillustrated
temperature sensor.
[0062] The Processing Gas Supply Unit and the Inactive Gas Supply
Unit
[0063] A channel-shaped preliminary chamber 21 is formed such that
it extends long in the vertical direction projecting from the side
wall of the inner tube 2 outward in the radial direction of the
inner tube 2 on the side wall of the inner tube 2 (at the position
on the opposite side of, i.e., at the position turned 180 degrees
with respect to, an exhaust hole 25 which will be described later).
A side wall 26 of the preliminary chamber 21 constitutes a part of
the side wall of the inner tube 2. In addition, the preliminary
chamber 21 is configured such that the inner wall of the
preliminary chamber 21 forms a part of the inner wall of the
processing chamber 4. Inside the preliminary chamber 21, there are
provided processing gas supply nozzles 22a, 22b which extend in the
stacking direction of the wafers 10 running along the inner wall of
the preliminary chamber 21 (that is, the inner wall of the
processing chamber 4), and supply a processing gas to the inside of
the processing chamber 4. In addition, inside the preliminary
chamber 21, there are provided a pair of inactive gas supply
nozzles 22c, 22d, which are provided so as to extend in the
stacking direction of the wafers 10 running along the inner wall of
the preliminary chamber 21 (that is, the inner wall of the
processing chamber 4) and to sandwich the processing gas supply
nozzles 22a, 22b from both sides thereof along the circumferential
direction of the wafers 10, and which supply an inactive gas to the
inside of the processing chamber 4.
[0064] Processing gas introduction port sections 23a, 23b which are
the end sections at the upstream side of the processing gas supply
nozzles 22a, 22b, and inactive gas introduction port sections 23c,
23d which are the end sections at the upstream side of the inactive
gas supply nozzles 22c, 22d, respectively, pass through the side
wall of the manifold 6 outward in the radial direction of the
manifold 6 and project to the outside of the process tube 1.
[0065] Processing gas supply tubes 25a, 25b, which serve as the
processing gas supply lines, are connected to the processing gas
introduction port sections 23a, 23b, respectively.
[0066] In the processing gas supply tube 25a, a processing gas
supply source 28a, an MFC (mass flow controller) 27a which serves
as a flow quantity control device, and an on-off valve 26a are
provided in this sequence from the upstream side. The processing
gas supply source 28a supplies a processing gas such as a gas
(TEMAH gas or TEMAZ gas) obtained by gasifying, for example, TEMAH
(Hf[NCH.sub.3C.sub.2H.sub.5].sub.4, tetrakis ethyl methyl amino
hafnium), TEMAZ[NCH.sub.3C.sub.2H.sub.5].sub.4, tetrakis ethyl
methyl amino zirconium) as the liquid raw materials. As described
above, as the processing gas to be sandwiched from both sides
thereof by the inactive gas, a gas of which a thermal decomposition
temperature is lower than a processing temperature (deposition
temperature), for example, a gas obtained by gasifying TEMAH or
TEMAZ (TEMAH gas or TEMAZ gas), or the like is used. Note that, a
carrier gas supply tube which is not shown is connected to the
processing gas supply tube 25a downstream of the on-off valve 26a.
The processing gas supply tube 25a is configured so as to enable
diluting the processing gas by supplying an N.sub.2 gas as the
carrier gas from the carrier gas supply tube, thereby promoting
supply of the processing gas to the inside of the processing
chamber 4 and diffusion of the processing gas inside the processing
chamber 4.
[0067] Meanwhile, in the processing gas supply tube 25b, a
processing gas supply source 28b which supplies a processing gas,
for example, an O.sub.3 (ozone) gas, or the like, an MFC (mass flow
controller) 27b as a flow quantity control device, and an on-off
valve 26b are provided in this sequence from the upstream side.
Note that, a carrier gas supply tube which is not shown is
connected to the processing gas supply tube 25b downstream of the
on-off valve 26b. The processing gas supply tube 25b is configured
so as to enable diluting the processing gas by supplying an N.sub.2
gas as the carrier gas from the carrier gas supply tube, thereby
promoting supply of the processing gas to the inside of the
processing chamber 4 and diffusion of the processing gas inside the
processing chamber 4.
[0068] Inactive gas supply tubes 25c, 25d, as the inactive gas
supply lines, are connected to the inactive gas introduction port
sections 23c, 23d, respectively. In the inactive gas supply tubes
25c, 25d, there are provided inactive gas supply sources 28c, 28d
which supply an inactive gas, for example, an N.sub.2 gas, an Ar
gas, an He gas, or the like, MFCs (mass flow controllers) 27c, 27d
as flow quantity control devices, and on-off valves 26c, 26d,
respectively, in this sequence from the upstream side.
[0069] A processing gas supply unit according to the present
embodiment is constituted mainly by the processing gas supply
nozzles 22a, 22b, the processing gas supply tubes 25a, 25b, the
processing gas supply sources 28a, 28b, the MFCs 27a, 27b, the
on-off valves 26a, 26b, and the unillustrated two carrier gas
supply tubes. In addition, an inactive gas supply unit according to
the present embodiment is constituted mainly the inactive gas
supply nozzles 22c, 22d, the inactive gas supply tubes 25c, 25d,
the inactive gas supply sources 28c, 28d, the MFCs 27c, 27d, and
the on-off valves 26c, 26d.
[0070] A gas supply and flow quantity control section 235 is
electrically connected to the MFCs 27a, 27b, 27c, 27d and the
on-off valves 26a, 26b, 26c, 26d. The gas supply and flow quantity
control section 235 is configured to control the MFCs 27a, 27b,
27c, 27d and the on-off valves 26a, 26b, 26c, 26d, such that the
type of the gas, to be supplied to the inside of the processing
chamber 4 at each of steps which will be described later, is a
desired gas type at a desired timing, the flow quantity of the gas
to be supplied is a desired quantity at a desired timing, and the
concentration of the processing gas with respect to the inactive
gas is a desired concentration at a desired timing.
[0071] A plurality of ejection ports 24a, 24b are provided so as to
be aligned in the vertical direction at cylindrical sections of the
processing gas supply nozzles 22a, 22b inside the processing
chamber 4. A plurality of ejection ports 24c, 24d are provided so
as to be aligned in the vertical direction at cylindrical sections
of the inactive gas supply nozzles 22c, 22d inside the processing
chamber 4.
[0072] The processing gas supply nozzles 22a, 22b and the inactive
gas supply nozzles 22c, 22d are provided inside the preliminary
chamber 21, whereby the ejection ports 24a, 24b of the processing
gas supply nozzles 22a, 22b and the ejection ports 24c, 24d of the
inactive gas supply nozzles 22c, 22d are in the state where the
ejection ports 24a, 24b, 24c, 24d are located outward in the radial
direction of the inner tube 2 with respect to an inner peripheral
surface of the inner tube 2.
[0073] The ejection ports 24a, 24b, 24c, 24d are configured such
that the number thereof matches, for example, the number of the
wafers 10 held by the boat 11. The height positions of the ejection
ports 24a, 24b, 24c, 24d are set to positions, where, for example,
each ejection port faces a space between the adjacent upper and
lower wafers 10 held by the boat 11. Note that, the apertures of
the ejection ports 24a, 24b, 24c, 24d may be set to different sizes
such that the gas supply amounts to each of the wafers 10 are made
uniform. Note that, the ejection ports 24a, 24b, 24c, 24d may be
provided such that one ejection port corresponds to a plurality of
the wafers 10 (for example, one ejection port corresponds to the
several wafers 10).
[0074] At the position opposing the processing gas supply nozzles
22a, 22b, that is, at the position on the opposite side, i.e., at
the position turned by 180 degrees with respect to the preliminary
chamber 21 on the side wall of the inner tube 2, the exhaust hole
25, for example, a slit-shaped through hole, is formed in an
elongated shape in the vertical direction. The inside of the
processing chamber 4 and the inside of the exhaust passage 8 are
communicated with each other via the exhaust hole 25. Accordingly,
the exhaust hole 25 is configured such that the processing gas
supplied from the ejection ports 24a, 24b of the processing gas
supply nozzles 22a, 22b to the inside of the processing chamber 4,
and the processing gas supplied from the ejection ports 24a, 24b of
the inactive gas supply nozzles 22c, 22d to the inside of the
processing chamber 4, flow to the inside of the exhaust passage 8
via the exhaust hole 25, thereafter flow to the inside of the
exhaust tube 7a via the exhaust port 7, and are released to the
outside of the processing furnace 202. Note that, the exhaust hole
25 is not limited to a slit-shaped through hole, and instead it may
be configured as a plurality of holes.
[0075] Note that, as shown in FIG. 2, a straight line connecting
the processing gas supply nozzle 22a and the exhaust hole 25 and a
first straight line connecting the processing gas supply nozzle 22b
and the exhaust hole 25 are respectively configured to pass the
vicinity of the center of each wafer 10. Note that, the
orientations of the ejection ports 24a, 24b are set substantially
parallel to the first straight line. In addition, a second straight
line connecting the inactive gas supply nozzles 22c and the exhaust
hole 25 and a third straight line connecting the inactive gas
supply nozzles 22c and the exhaust hole 25 are configured to
sandwich the straight line connecting the processing gas supply
nozzle 22a and the exhaust hole 25 and the first straight line
connecting the processing gas supply nozzles 22b and the exhaust
hole 25 from both sides thereof. Note that, the orientations of the
ejection ports 24c, 24d may be set such that they are angled
outward with respect to the straight line or such that they are
substantially parallel to the straight lines. In other words, the
ejection port 24c may be configured such that it is opened in the
outward orientation with respect to the second straight line or
such that it is opened substantially parallel to the second
straight line. In addition, the orientation of the ejection port
24d may be configured such that it is opened in the outward
orientation with respect to the third straight line or such that it
is opened substantially parallel to the third straight line.
[0076] Accordingly, when both the processing gas and the inactive
gas are to be simultaneously supplied to the inside of the
processing chamber 4 as shown in FIG. 3, gas flows 30a, 30b of the
processing gas supplied from the ejection ports 24a, 24b of the
processing gas supply nozzles 22a, 22b, respectively, to the inside
of the processing chamber 4 is sandwiched from both sides thereof
by of gas flows 30c, 30d of the inactive gas supplied from the
ejection ports 24c, 24d of the inactive gas supply nozzles 22c,
22d, respectively, to the inside of the processing chamber 4,
whereby flow passages thereof are restricted. For example, when the
inactive gas is supplied to the clearance between the
circumferential edge of each wafer 10 and the processing chamber 4,
the pressure in the area becomes relatively higher, and thus the
processing gas is suppressed from flowing to the clearance between
the circumferential edge of each wafer 10 and the processing
chamber 4. As a result of this, supply of the processing gas to the
vicinity of the center of each wafer 10 is promoted, and the supply
amounts of the processing gas to the vicinity of the outer
periphery and to the vicinity of the center of each wafer 10 are
made more uniform. In addition, the processing gas is diluted by
the inactive gas in the clearance between the circumferential edge
of each wafer 10 and the processing chamber 4, whereby formation of
too thick a film in the vicinity of the outer periphery of each
wafer 10 is suppressed.
[0077] The Controller
[0078] The gas supply and flow quantity control section 235, the
pressure control section 236, the drive control section 237, and
the temperature control section 238 constitutes also an operating
section and the input-output section, and are electrically
connected to a main control section 239 which controls the entire
substrate processing apparatus. The gas supply and flow quantity
control section 235, the pressure control section 236, the drive
control section 237, the temperature control section 238, and the
main control section 239 as described above are configured as the
controller 240.
4. The Substrate Processing Step
[0079] One of manufacturing processes for a semiconductor device
(device) carried out by the above-described substrate processing
apparatus 101 will now be described. As described above, as the
processing gas to be sandwiched from both sides thereof by the
inactive gas, a gas of which a thermal decomposition temperature is
lower than a processing temperature (deposition temperature), for
example, a gas obtained by gasifying TEMAH or TEMAZ (TEMAH gas or
TEMAZ gas), or the like, may be used. Hereinafter, description will
be given on the case where an HfO.sub.2 film is formed with use of
the TEMAH gas and the O.sub.3 gas as the processing gas in
accordance with the ALD method. In the following description, the
operation of the individual sections constituting the substrate
processing apparatus 101 is controlled by the controller 240.
[0080] The ALD (Atomic Layer Deposition) method which is one of the
CVD (Chemical Vapor Deposition) methods is a technique for,
supplying alternately one by one at least two types of processing
gases which react with each other and which are used for film
formation, onto the substrate, under certain deposition conditions
(temperature, time period, or the like), adsorbing them onto the
substrate in the unit of 1 atom, and performing film formation with
use of the surface reaction. At this time, the film thickness is
controlled on the basis of the number of cycles in which a reactive
gas is supplied. (For example, when the deposition rate is assumed
to be 1 .ANG./cycle, film formation is performed in 20 cycles for
forming a film of 20 .ANG.A.) For example, in the case where an
HFO.sub.2 film is formed in accordance with the ALD method, a
high-quality film can be formed at a low temperature of 180 to
250.degree. C. with use of a TEMAH (Hf
[NCH.sub.3C.sub.2H.sub.5].sub.4, tetrakis ethyl methyl amino
hafnium) gas and an O.sub.3 (ozone) gas.
[0081] First of all, as described above, the boat 11 is charged
with the group of wafers 10 to be processed, and loaded to the
inside of the processing chamber 4. After the boat 11 is loaded to
the inside of the processing chamber 4, when the pressure in the
processing chamber 4 becomes within the range of 10 to 1000 Pa, for
example, becomes 50 Pa and the temperature inside the processing
chamber 4 becomes within the range of 180 to 250.degree. C., for
example, becomes 220.degree. C., and a cycle, consisting of four
steps (Steps 1 to 4) as shown below, is repeated for a certain
number of times. Note that, while the following Steps 1 to 4 are
executed, the flow quantity of the gases supplied to the surface of
each wafer 10 can be made more uniform by rotating the rotating
mechanism 254.
[0082] Step 1
[0083] Both the on-off valve 26a in the processing gas supply tube
25a and the APC valve 7b in the exhaust tube 7a are opened, and
then the TEMAH gas as the processing gas is supplied from the
ejection port 24a of the processing gas supply nozzle 22a to the
inside of the processing chamber 4, while the inside of the
processing chamber 4 is exhausted by the vacuum pump 7c. The TEMAH
gas is supplied, after being diluted by a carrier gas (N.sub.2 gas)
supplied from the carrier gas supply tube which is not shown.
[0084] Note that, the TEMAH gas is a gas which greatly affects the
in-plane uniformity of substrate processing (in-plane uniformity of
thickness of the HfO.sub.2 film formed on the surface of each wafer
10). Accordingly, in Step 1 according to the present embodiment, at
the same time when the TEMAH gas is supplied to the inside of the
processing chamber 4, the on-off valves 26c, 26d in the inactive
gas supply tubes 25c, 25d are opened, respectively, and whereby the
N.sub.2 gas as the inactive gas is supplied from both the ejection
ports 24c, 24d of the inactive gas supply nozzles 22c, 22d to the
inside of the processing chamber 4, respectively. As a result of
this, the TEMAH gas supplied from the ejection port 24a of the
processing gas supply nozzle 22a to the inside of the processing
chamber 4 is sandwiched from both sides thereof, by the N.sub.2 gas
supplied from both the ejection ports 24c, 24c of the inactive gas
supply nozzles 22c, 22d, respectively, to the inside of the
processing chamber 4, whereby the flow passage of the TEMAH gas is
restricted. For example, when the inactive gas is supplied to the
clearance between the circumferential edge of each wafer 10 and the
processing chamber 4, the pressure in the area becomes relatively
higher, and thus the TEMAH gas is suppressed from flowing (being
released) to the clearance between the circumferential edge of each
wafer 10 and the processing chamber 4. As a result of this, supply
of the TEMAH gas to the vicinity of the center of each wafer 10 is
promoted, and the supply amounts of the TEMAH gas to the vicinity
of the outer periphery and to the vicinity of the center of each
wafer 10 are made more uniform. In addition, the TEMAH gas is
diluted by the N.sub.2 gas in the clearance between the
circumferential edge of each wafer 10 and the processing chamber 4,
whereby formation of too thick a film in the vicinity of the outer
periphery of each wafer 10 is suppressed. As described above, in
Step 1, the inactive gas (N.sub.2 gas) supplied from the inactive
gas supply tubes 25c, 25d functions as the assist gas which
restricts the flow passage of the processing gas, and make the
supply amount of the processing gas to the wafers 10 more
uniform.
[0085] Note that, when the TEMAH gas is supplied from the
processing gas supply nozzle 22a, it is preferable that the N.sub.2
gas be supplied from the inactive gas supply nozzles 22c, 22d in
the flow quantity which is equal to or greater than the flow
quantity of the TEMAH gas supplied from the processing gas supply
nozzle 22a. In other words, it is preferable that both the flow
quantity of the N.sub.2 gas supplied from the ejection port 24c of
the inactive gas supply nozzle 22c and the flow quantity of the
N.sub.2 gas supplied from the ejection port 24d of the inactive gas
supply nozzle 22d be equal to or greater than the flow quantity of
the TEMAH gas supplied from the ejection port 24a of the processing
gas supply nozzle 22a. The flow quantity of the TEMAH gas and the
flow quantities of the N.sub.2 gas are controlled by the MFCs 27a,
27c, 27d, respectively. As a result of this, supply of the TEMAH
gas to the vicinity of the center of each wafer 10 is further
promoted. In addition, dilution of the TEMAH gas by the N.sub.2 gas
in the clearance between the circumferential edge of each wafer 10
and the processing chamber 4 is further promoted.
[0086] During execution of Step 1, the pressure in the processing
chamber 4 is adjusted so as to be within the range of 20 to 900 Pa,
for example, to be 50 Pa. In addition, the supply flow quantity of
the TEMAH gas from the processing gas supply nozzle 22a is adjusted
so as to be within the range of 0.01 to 0.35 times/min, for
example, to be 0.3 g/min. The supply flow quantity of the N.sub.2
gas (carrier gas) from the carrier gas supply tube (not shown)
connected to the processing gas supply tube 25a is adjusted so as
to be within the range of 0.1 to 0.5 g/slm, for example, to be 10
slm. The supply flow quantities of the N.sub.2 gas (assist gas)
from the inactive gas supply nozzles 22c, 22d are respectively
adjusted so as to be within the range of 20 to 30 slm, for example,
to be 30 slm. The temperature in the processing chamber 4 is
adjusted so as to be within the range of 180 to 250.degree. C., for
example, to be 220.degree. C. In addition, the time period during
which the wafers 10 are exposed to the TEMAH gas (execution time of
Step 1) is set to be within the range of 30 to 180 seconds, for
example, to be 120 seconds.
[0087] Supplying of the TEMAH gas to the inside of the processing
chamber 4 causes the surface reaction (chemical adsorption) of gas
molecules of the TEMAH gas with the surface section such as a
primer film on the wafer 10.
[0088] Step 2
[0089] The on-off valve 26a in the processing gas supply tube 25a
is closed so as to stop supply of the TEMAH gas to the inside of
the processing chamber 4. At this time, with the APC valve 7b in
the exhaust tube 7a kept open, the inside of the processing chamber
4 is exhausted by the vacuum pump 7c such that the pressure therein
becomes, for example, 20 Pa or less, whereby the remaining TEMAH
gas is purged from the inside of the processing chamber 4. In
addition, if the on-off valves 26c, 26d in the inactive gas supply
tubes 25c, 25d are opened, respectively, and whereby the N.sub.2
gas is supplied to the inside of the processing chamber 4, the
effect of purging the remaining TEMAH gas from inside of the
processing chamber 4 will be further enhanced. In Step 2, the
N.sub.2 gas supplied from the inactive gas supply tubes 25c, 25d
functions as the purge gas which promotes release of the remaining
gas in the processing chamber 4.
[0090] During execution of Step 2, the pressure in the processing
chamber 4 is adjusted to be, for example, 20 Pa or less. In
addition, the supply flow quantities of the N.sub.2 gas (purge gas)
from the inactive gas supply nozzles 22c, 22d, are respectively
adjusted so as to be within the range of 0.5 to 20 slm, for
example, to be 12 slm. The temperature in the processing chamber 4
is adjusted so as to be within the range of 180 to 250.degree. C.,
for example, to be 220.degree. C. In addition, the execution time
of Step 2 is set to be within the range of 30 to 150 seconds, for
example, to be 60 seconds.
[0091] Step 3
[0092] With the APC valve 7b in the exhaust tube 7a being kept
open, the on-off valve 26b in the processing gas supply tube 25b is
opened, and whereby an O.sub.3 gas as the processing gas is
supplied from the ejection port 24b of the processing gas supply
nozzle 22b to the inside of the processing chamber 4, while the
inside of the processing chamber 4 is exhausted by the vacuum pump
7c. The O.sub.3 gas is supplied, after being diluted by the carrier
gas (N.sub.2 gas) supplied from the carrier gas supply tube which
is not shown.
[0093] Note that, the O.sub.3 gas is a gas which does not greatly
affect the in-plane uniformity of substrate processing (in-plane
uniformity of thickness of the HfO.sub.2 film formed on the surface
of each wafer 10). Accordingly, in Step 3 according to the present
embodiment, the N.sub.2 gas (assist gas) should not be supplied
from the inactive gas supply nozzles 22c, 22d. However, in the case
where the processing gas supplied in Step 3 is a gas which affects
the in-plane uniformity of substrate processing, it is preferable
that the N.sub.2 gas (assist gas) be supplied from the inactive gas
supply nozzles 22c, 22d, also in Step 3 like Step 1. In addition,
even in the case where the O.sub.3 gas is supplied, the N.sub.2 gas
(assist gas) may be supplied from the inactive gas supply nozzles
22c, 22d.
[0094] During execution of Step 3, the pressure in the processing
chamber 4 is adjusted so as to be within the range of 20 to 900 Pa,
for example, to be 50 Pa. In addition, the supply flow quantity of
the O.sub.3 gas from the processing gas supply nozzle 22b is
adjusted so as to be within the range of 6 to 20 slm, for example,
to be 17 slm. The supply flow quantity of the N.sub.2 gas (carrier
gas) from the carrier gas supply tube (not shown) connected to the
processing gas supply tube 25b is adjusted so as to be within the
range of 0 to 2 slm, for example, to be 0.5 slm. The temperature in
the processing chamber 4 is adjusted so as to be within the range
of 180 to 250.degree. C., for example, to be 220.degree. C. In
addition, the time period during which the wafers 10 are exposed to
the TEMAH gas (execution time of Step 3) is set to be within the
range of 10 to 300 seconds, for example, to be 120 seconds.
[0095] Supply of the O.sub.3 gas to the inside of the processing
chamber 4 causes the surface reaction of the TEMAH gas which has
been chemically adsorbed on the surface of each wafer 10 with the
O.sub.3 gas, whereby an HFO.sub.2 film is formed on the wafer
10.
[0096] Step 4
[0097] The on-off valve 26b in the processing gas supply tube 25b
is closed so as to stop supply of the O.sub.3 gas to the inside of
the processing chamber 4. At this time, with the APC valve 7b in
the exhaust tube 7a kept open, the inside of the processing chamber
4 is exhausted by the vacuum pump 7c such that the pressure therein
becomes, for example, 20 Pa or less, whereby the remaining O.sub.3
gas is purged from the inside of the processing chamber 4. In
addition, if the on-off valves 26c, 26d in the inactive gas supply
tubes 25c, 25d are opened, respectively, and whereby the N.sub.2
gas is supplied to the inside of the processing chamber 4, the
effect of purging the remaining O.sub.3 gas inside of the
processing chamber 4 will be further enhanced. In Step 4, the
N.sub.2 gas supplied from the inactive gas supply tubes 25c, 25d
functions as the purge gas which promotes release of the remaining
gas in the processing chamber 4.
[0098] During execution of Step 4, the pressure in the processing
chamber 4 is adjusted so as to be, for example, 20 Pa or less. In
addition, the supply flow quantities of the N.sub.2 gas (purge gas)
from the inactive gas supply nozzles 22c, 22d, are respectively
adjusted so as to be within the range of 0.5 to 20 slm, for
example, to be 12 slm. The temperature in the processing chamber 4
is adjusted so as to be within the range of 180 to 250.degree. C.,
for example, to be 220.degree. C. In addition, the execution time
of Step 2 is set to be within the range of 30 to 150 seconds, for
example, to be 60 seconds.
[0099] Next, with the above-described Steps 1 to 4 being set as one
cycle, the cycle is repeated multiple times, whereby an HfO.sub.2
film with a certain film thickness is deposited on each wafer 10.
Subsequently, the boat 11 holding the processed group of wafers 10
is unloaded from the inside of the processing chamber 4, whereby
the substrate processing step according to the present embodiment
is terminated.
5. Advantageous Effects of the Present Embodiment
[0100] The present embodiment exerts one or a plurality of
advantageous effects as described below.
[0101] According to the present embodiment, in the above-described
Step 1, the TEMAH gas supplied from the ejection port 24a of the
processing gas supply nozzle 22a to the inside of the processing
chamber 4 is sandwiched from both sides thereof by the N.sub.2 gas
supplied from the ejection ports 24c, 24d of the inactive gas
supply nozzles 22c, 22d, respectively, to the inside of the
processing chamber 4, whereby the flow passage of the TEMAH gas is
restricted. For example, when the N.sub.2 gas is supplied to the
clearance between the circumferential edge of each wafer 10 and the
processing chamber 4, the pressure in the area becomes relatively
higher in the area, and thus the TEMAH gas is suppressed from
flowing to the clearance between the circumferential edge of each
wafer 10 and the processing chamber 4. As a result of this, supply
of the TEMAH gas to the vicinity of the center of each wafer 10 is
promoted, whereby the supply amounts of the TEMAH gas to the
vicinity of the outer periphery and to the vicinity of the center
of each wafer 10 are made more uniform. In addition, the TEMAH gas
is diluted by the N.sub.2 gas in the clearance between the
circumferential edge of each wafer 10 and the processing chamber 4,
whereby formation of too thick a film in the vicinity of the outer
periphery of each wafer 10 is suppressed.
[0102] Note that, in the present embodiment, when the TEMAH gas is
supplied from the processing gas supply nozzle 22a, if the N.sub.2
gas is supplied from the inactive gas supply nozzles 22c, 22d in
the flow quantity which is equal to or greater than the flow
quantity of the TEMAH gas supplied from the processing gas supply
nozzle 22a, supply of the TEMAH gas to the vicinity of the center
of each wafer 10 will be further promoted. In addition, dilution of
the TEMAH gas by the N.sub.2 gas in the clearance between the
circumferential edge of each wafer 10 and the processing chamber 4
is further promoted, whereby formation of too thick an HfO.sub.2
film in the vicinity of the outer periphery of each wafer 10 is
suppressed.
[0103] In addition, according to the present embodiment, the
O.sub.3 gas is a gas which does not greatly affect the in-plane
uniformity of thickness of the HfO.sub.2 film formed on the surface
of the each wafer 10. Therefore, in Step 3, the N.sub.2 gas (assist
gas) should not be supplied from the inactive gas supply nozzles
22c, 22d. However, the N.sub.2 gas (assist gas) may be supplied
from the inactive gas supply nozzles 22c, 22d also in Step 3, like
Step 1.
[0104] In such a case, the O.sub.3 gas supplied from the ejection
port 24b of the processing gas supply nozzle 22b to the inside of
the processing chamber 4 is sandwiched from both sides thereof by
the N.sub.2 gas supplied from the ejection ports 24c, 24d of the
inactive gas supply nozzles 22c, 22d to the inside of the
processing chamber 4, whereby the flow passage of the O.sub.3 gas
is restricted. For example, when the N.sub.2 gas is supplied to the
clearance between the circumferential edge of each wafer 10 and the
processing chamber 4, the pressure in the area becomes relatively
higher, whereby the O.sub.3 gas is suppressed from flowing in the
clearance between the circumferential edge of each wafer 10 and the
processing chamber 4. As a result of this, supply of the O.sub.3
gas to the vicinity of the center of each wafer 10 is promoted,
whereby the supply amounts of the O.sub.3 gas to the vicinity of
the outer periphery and to the vicinity of the center of each wafer
10 are made more uniform. In addition, the O.sub.3 gas is diluted
by the N.sub.2 gas in the clearance between the circumferential
edge of each wafer 10 and the processing chamber 4, whereby
formation of too thick a film in the vicinity of the outer
periphery of each wafer 10 is suppressed.
[0105] Note that, in the present embodiment, when the O.sub.3 gas
is supplied from the processing gas supply nozzles 22a, if the
N.sub.2 gas is supplied from the inactive gas supply nozzles 22c,
22d in the flow quantity which is equal to or greater than the flow
quantity of the O.sub.3 gas supplied from the processing gas supply
nozzles 22b, the O.sub.3 gas supplied to the vicinity of the center
of each wafer 10 will be further promoted. In addition, dilution of
the O.sub.3 gas by the N.sub.2 gas is further promoted in the
clearance between the circumferential edge of each wafer 10 and the
processing chamber 4, whereby formation of too thick an HfO.sub.2
film in the vicinity of the outer periphery of each wafer 10 is
suppressed.
[0106] In addition, in Steps 2, 4 of the present embodiment, if the
on-off valves 26c, 26d in the inactive gas supply tubes 25c, 25d
are opened, respectively, and whereby the N.sub.2 gas is supplied
to the inside of the processing chamber 4, the effect of purging
the remaining TEMAH gas and O.sub.3 gas from the inside of the
processing chamber 4 will be further enhanced. As a result of this,
the time period required for execution of Steps 2, 4 can be
reduced, and productivity of the substrate processing can be
enhanced.
[0107] In addition, according to the present embodiment, there is
no need for providing ring-shaped straightening vanes respectively
between the circumferential edge of each wafer 10 supported by the
boat 11 and the inner wall of the processing chamber 4.
Accordingly, there is no need for securing a wide stacking pitch of
the wafers 10, decrease in the number of substrates which can be
collectively processed can be suppressed. As a result of this,
productivity of the substrate processing can be enhanced.
[0108] In addition, according to the present embodiment, there is
no need for providing ring-shaped straightening vanes,
respectively, between the circumferential edges of the wafers 10
supported by the boat 11 and the inner wall of the processing
chamber 4. Accordingly, the production cost of the boat 11 and the
substrate processing cost can be reduced.
The Second Embodiment of the Present Invention
[0109] In the above-described embodiment, the at least one
processing gas supply nozzles 22a, 22b supplying the processing gas
to the inside of the processing chamber 4 and the pair of the
inactive gas supply nozzles 22c, 22d which are provided so as to
sandwich the processing gas supply nozzles 22a, 22b from both sides
thereof and which supply the inactive gas to the inside of the
processing chamber 4, are provided individually. In addition, the
processing gas (for example, TEMAH gas) supplied from the
processing gas supply nozzle 22a and the processing gas (for
example, O.sub.3 gas) supplied from the processing gas supply
nozzle 22b are respectively sandwiched, from both sides thereof, by
the inactive gas from the inactive gas supply nozzles 22c, 22d.
[0110] However, the present invention is not limited to this
embodiment. Specifically, in the case where only the in-plane
uniformity of supply amount of either one type of the processing
gas among a plurality of types of the processing gases supplied
from at least one processing gas supply nozzle affects the in-plane
uniformity of substrate processing (i.e., in the case where the
in-plane uniformity of supply amount of other processing gas does
not greatly affect the in-plane uniformity of substrate
processing), only the processing gas which affects the in-plane
uniformity of substrate processing should be sandwiched from both
sides thereof by the inactive gas, and the processing gas which
does not greatly affect the in-plane uniformity of substrate
processing need not be sandwiched from both sides thereof by the
inactive gas.
[0111] In this case, when the processing gas is supplied from the
other processing gas supply nozzle (i.e., the processing gas supply
nozzle which supplies the processing gas affecting the in-plane
uniformity of substrate processing), at least one processing gas
supply nozzle (the processing gas supply nozzle which supplies the
processing gas which does not greatly affect the in-plane
uniformity of substrate processing) of the at least one processing
gas supply nozzle may be configured to supply the inactive gas in
the flow quantity which is equal to or greater than the flow
quantity of the processing gas supplied from the other processing
gas supply nozzle.
[0112] For example, in the case where the in-plane uniformity of
supply amount of the TEMAH gas greatly affects the in-plane
uniformity of substrate processing while the in-plane uniformity of
supply amount of the O.sub.3 gas does not greatly affect the
in-plane uniformity of substrate processing, only the TEMAH gas
should be sandwiched from both sides thereof by the N.sub.2 gas and
the O.sub.3 gas need not be sandwiched from both sides thereof by
the N.sub.2 gas. In addition, the inactive gas supply nozzles 22c
and the processing gas supply nozzles 22b may be configured such
that they supply the N.sub.2 gas, respectively, in the flow
quantity which is equal to or greater than the flow quantity of the
TEMAH gas supplied from the processing gas supply nozzles 22a, when
the TEMAH gas is supplied from the processing gas supply nozzle
22a. In addition, if the inactive gas supply nozzle 22d is not
provided, the structure of the substrate processing apparatus can
be simplified and the substrate processing cost can be reduced.
The Third Embodiment of the Present Invention
[0113] Hereinafter, the third embodiment of the present invention
will be described with reference to FIG. 10. The present embodiment
is different from the above-described embodiments in that the
inactive gas ejection ports 24c, 24d are opened so as to inject the
inactive gas to a space (clearance) between the inner wall of the
processing chamber 4 and the outer periphery section of the each
wafer 10, rather than to the center direction of each wafer 10. The
other structures are the same as those of the above-described
embodiments.
[0114] A straight line connecting the processing gas supply nozzle
22a and an exhaust port 25 and a straight line connecting the
processing gas supply nozzle 22b and the exhaust port 25 are
respectively configured to pass the vicinity of the center of each
wafer 10. Note that, the orientations of the processing gas
ejection ports 24a, 24b are set substantially parallel to these
straight lines. In other words, the processing gas ejection ports
24a, 24b are opened so as to supply the processing gas to the
center of each wafer 10. In addition, a straight line connecting
the inactive gas supply nozzle 22c and the exhaust port 25 and a
straight line connecting the inactive gas supply nozzle 22c and the
exhaust port 25 are configured to sandwich both the straight line
connecting the processing gas supply nozzle 22a and the exhaust
port 25 and the straight line connecting the processing gas supply
nozzles 22b and the exhaust port 25 from both sides thereof. Note
that, the orientations of the inactive gas ejection ports 24c, 24d
are set such that they are angled outward with respect to the
straight lines. In addition, the inactive gas ejection ports 24c,
24d are opened so as to inject the inactive gas to the space
(clearance) between the inner wall of the processing chamber 4 and
the outer periphery section of each wafer 10, rather than to the
center direction of each wafer 10. Note that, the side wall of the
preliminary chamber 21 is configured to be substantially parallel
to the orientations of the inactive gas ejection ports 24c,
24d.
[0115] Accordingly, as shown in FIG. 10, when the processing gas
and the inactive gas are configured to be simultaneously supplied
to the inside of the processing chamber 4, the gas flows (arrows
shown by solid lines in FIG. 10) of the processing gas supplied
from the processing gas ejection ports 24a, 24b of the processing
gas supply nozzles 22a, 22b, respectively, to the inside of the
processing chamber 4 are sandwiched, from both sides thereof, by
the gas flows (arrows shown by solid lines in FIG. 10) of the
inactive gas supplied from the inactive gas ejection ports 24c, 24d
of the inactive gas supply nozzles 22c, 22d, respectively, to the
inside of the processing chamber 4, whereby the flow passages of
the processing gas are restricted. For example, when the inactive
gas is supplied to the space between the circumferential edge of
each wafer 10 and the processing chamber 4, the pressure in the
area becomes relatively higher, whereby the processing gas is
suppressed from flowing to the clearance between the
circumferential edge of each wafer 10 and the processing chamber 4.
As a result of this, supply of the processing gas to the vicinity
of the center of each wafer 10 is promoted, whereby the supply
amounts of the processing gas to the vicinity of the outer
periphery and to the vicinity of the center of each wafer 10 are
made more uniform. In addition, the processing gas is diluted by
the inactive gas in the clearance between the circumferential edge
of each wafer 10 and the processing chamber 4, whereby formation of
too thick a film in the vicinity of the outer periphery of each
wafer 10 is suppressed.
[0116] In addition, the inactive gas ejection ports 24c, 24d of the
inactive gas supply nozzles 22c, 22d are respectively opened so as
to inject the inactive gas to a space between the inner wall of the
processing chamber 4 and the outer periphery section of each wafer
10, rather than to the center direction of each wafer 10.
Accordingly, the inactive gas supplied from the inactive gas
ejection ports 24c, 24d of the inactive gas supply nozzles 22c,
22d, respectively, to the inside of the processing chamber 4 mainly
flow to the space between the circumferential edge of each wafer 10
and the processing chamber 4, and hardly flows to the area where
the group of wafers 10 are held. As a result of this, dilution by
the inactive gas of the processing gas supplied to each wafer 10 is
suppressed, and decrease in deposition rate is avoided.
[0117] In addition, since inflow of the TEMAH gas and the O.sub.3
gas to the clearance between the circumferential edge of each wafer
10 and the processing chamber 4 is suppressed, deposition on the
side wall of the processing chamber 4 (the side wall of the inner
tube 2), adhesion of raw material components, and generation of
foreign matters inside the processing chamber 4 are suppressed.
Accordingly, the maintenance cycle of the substrate processing
apparatus 101 is extended, whereby productivity of the substrate
processing apparatus 101 can be enhanced.
The Fourth Embodiment of the Present Invention
[0118] Hereinafter, the fourth embodiment of the present invention
will be described with reference to FIG. 11. The present embodiment
is different from the above-described embodiments in that the
processing chamber 4 has straightening vanes 31c, 31d therein. The
other structures are the same as those of the above-described
embodiment.
[0119] The straightening vanes 31c, 31d are provided so as to
extend in the vertical direction outside of the inactive gas supply
nozzles 22c, 22d. The inactive gas supply nozzles 22c, 22d are on
the inner side (the wafer 10 side) of the processing chamber 4 with
respect to the inactive gas ejection ports 24c, 24d serving as the
inactive gas ejection ports. Specifically, the straightening vane
31c is provided so as to extend in the vertical direction between
the inactive gas supply nozzle 22c and each wafer 10, and to be
substantially parallel to the orientation of the inactive gas
ejection port 24c. The straightening vane 31d is provided so as to
extend in the vertical direction between the inactive gas supply
nozzle 22d and each wafer 10, and to be substantially parallel to
the orientation of the inactive gas ejection port 24d. A gas flow
passage for guiding a flow of the inactive gas supplied from the
inactive gas ejection port 24cis formed between the straightening
vane 31c and the side wall of the preliminary chamber 21, and a gas
flow passage for guiding a flow of the inactive gas supplied from
the inactive gas ejection port 24d is formed between the
straightening vane 31d and the side wall of the preliminary chamber
21. The straightening vanes 31c, 31d may be installed to the
inactive gas supply nozzles 22c, 22d, respectively, or may be
directly installed to the inner wall of the inner tube 2, or the
like.
[0120] By the configuration as described above, inflow of the
inactive gas to the area where the group of wafers 10 are held is
further suppressed. As a result of this, dilution by the inactive
gas of the processing gas supplied to each wafer 10 is suppressed,
whereby decrease in deposition rate is further avoided.
The Fifth Embodiment of the Present Invention
[0121] Hereinafter, the fifth embodiment of the present invention
will be described with reference to FIG. 12. The present embodiment
is different from the above-described embodiments in that the
processing chamber 4 has a processing gas exhaust port 35 for
exhausting the processing gas, and inactive gas exhaust ports 35c,
35d for exhausting the inactive gas, respectively, in place of the
exhaust port 25. The other structures are the same as those of the
above-described embodiments.
[0122] The processing gas exhaust port 35 is configured to be
similar to the above-described exhaust port 25. Specifically, the
processing gas exhaust port 35 is formed in an elongated shape in
the vertical direction, as the slit-shaped through hole, at the
position on the opposite side of, i.e., at the position turned by
180 degrees with respect to the preliminary chamber 21, that is, at
a position on the exhaust port 7 side, on the side wall of the
inner tube 2. In addition, the inactive gas exhaust ports 35c, 35d
are respectively formed in elongated shapes in the vertical
direction, as the slit-shaped through holes, at positions where
they sandwich the processing gas exhaust port 35 from both sides
thereof.
[0123] By the structure as described above, the processing gas
supplied from the processing gas ejection ports 24a, 24b is
exhausted from the processing gas exhaust port 35, and the inactive
gas supplied from the inactive gas ejection ports 24c, 24d is
exhausted from the inactive gas exhaust ports 35c, 35d,
respectively. As a result of this, the gas flows in the vicinity of
the processing gas exhaust port 35, and the inactive gas exhaust
ports 35c, 35d, are made smoother, respectively.
Other Embodiments of the Present Invention
[0124] The present invention is not limited to the above-described
embodiments, and it is obvious that various modifications are
possible as long as they are not deviated from the summary of the
invention.
[0125] For example, the preliminary chamber 21 need not be provided
in the inner tube 2. That is, as illustrated in FIG. 9, the
processing gas supply nozzles 22a, 22b and the inactive gas supply
nozzles 22c, 22d may be located inward in the radial direction of
the inner tube 2 with respect to the inner peripheral surface of
the inner tube 2.
[0126] As described above, the number of the ejection ports 24a,
24b, 24c, 24d need not match the number of the wafers 10. For
example, the invention is not limited to the case where the
ejection ports 24a, 24b, 24c, 24d are provided at height positions,
where each ejection port faces a space between the adjacent upper
and lower wafers 10. (The same number as the number of wafers 10 of
the ejection ports are provided.) For example, one ejection port
may be provided for a plurality of the wafers 10.
[0127] In addition, as described above, the exhaust hole 25 formed
in the side wall of the inner tube 2 is not limited to a
slit-shaped through hole. The exhaust hole 25 may be configured as,
for example, a plurality of slot holes, circular holes, polygonal
holes, or the like. In the case where the exhaust hole 25 is
configured by a plurality of holes, the invention is limited to the
case where the number of the holes matches the number of the wafers
10. Instead, the number can be increased or decreased. For example,
the invention is not limited to the case where a plurality of holes
constituting the exhaust hole 25 are respectively provided at the
height positions corresponding to spaces between the stacked wafers
10. (The same number as the number of wafers 10 of the ejection
ports are provided.) For example, one hole may be provided for a
plurality of the wafers 10. In addition, in the case where the
exhaust hole 25 is configured as a series of slot holes (slits),
the width thereof may be increased or decreased from the top to the
bottom of the inner tube 2. In addition, in the case where the
exhaust hole 25 is configured by a plurality of holes, the
apertures of these plurality of holes may be increased or decreased
from the top to the bottom of the inner tube 2.
[0128] In the above-described embodiments, description is given on
the case where the processing is performed on the wafers 10.
However, the object of processing may be a photomask, print circuit
board, substrate, liquid crystal panel, compact disk, and magnetic
disk, or the like.
[0129] In the above-described embodiments, description is given on
deposition of a film in accordance with the ALD method. However,
the present invention is not limited to ALD, and is preferably
applicable to deposition of a film in accordance with the CVD
method. Furthermore, the substrate processing method according to
the present invention can be applied to overall substrate
processing methods such as an oxide film formation method,
diffusion method, or the like.
[0130] Hereinafter, an example of the present invention will be
described together with a comparative example. FIG. 8 is a table
chart showing a result of substrate processing according to an
example of the present invention. FIG. 7 s a table chart showing a
result of substrate processing according to a comparative example.
Note that, in the present example, the substrate processing
apparatus and the substrate processing step according to the first
embodiment are used.
[0131] In the example shown in FIG. 8, a Zr oxide film is formed in
accordance with the ALD method, by supplying an amine-based Zr raw
material gas, as the processing, gas from the processing gas supply
nozzle 22a, and supplying an O.sub.3 gas, as the processing gas,
from the processing gas supply nozzle 22b. The in-plane uniformity
of the film thickness of the Zr oxide film is greatly affected by
the in-plane uniformity of gas supply amount of the amine-based Zr
raw material. Accordingly, in the present example, the amine-based
Zr raw material gas was sandwiched from both sides thereof by an
N.sub.2 gas (inactive gas). Specifically, when the amine-based Zr
raw material gas was supplied from the processing gas supply nozzle
22d in Step 1, the N.sub.2 gas was supplied at the flow quantity of
30 slm from each of the inactive gas supply nozzle 22c and the
processing gas supply nozzle 22b. (Note that, the acceptable range
of the supply flow quantity of the N.sub.2 gas (inactive gas) is,
for example, 20 to 30 slm.) As a result, as shown in FIG. 7, for
the wafers 10 charged to the upper section inside the boat 11, the
mean film thickness of the Zr oxide film was 33.7 (.ANG.) and the
in-plane uniformly was .+-.3.9 (%). For the wafers 10 charged to
the middle section inside the boat 11, the mean film thickness of
the Zr oxide film was 33.6 (.ANG.) and the in-plane uniformly was
.+-.3.7 (%). For the wafers 10 charged to the lower section in the
boat 11, the mean film thickness of the Zr oxide film was 33.6
(.ANG.), and the in-plane uniformly was .+-.4.1 (%). It was
confirmed that the in-plane uniformity of substrate processing was
remarkably improved compared with the comparative example which
will be described later. In addition, the inter-wafer uniformly was
.+-.0.2 (%), based on which it was confirmed that inter-substrate
uniformity of substrate processing was remarkably improved compared
with the comparative example which will be described later.
[0132] In the comparative example shown in FIG. 7, the N.sub.2 gas
was not supplied from the inactive gas supply nozzles 22c, 22d or
the processing gas supply nozzle 22b, when the amine-based Zr raw
material gas was supplied from the processing gas supply nozzle 22a
in Step 1. Other conditions are substantially the same as those in
the example shown in FIG. 8. As a result, as shown in FIG. 7, for
the wafers 10 charged to the upper section inside the boat 11, the
mean film thickness of the Zr oxide film was 37.6 (.ANG.) and the
in-plane uniformly was .+-.9.7 (%). For the wafers 10 charged to
the middle section of the boat 11, the mean film thickness of the
Zr oxide film was 36.7 (.ANG.) and the in-plane uniformly was
.+-.8.5 (%). For the wafers 10 charged to the lower section in the
boat 11, the mean film thickness of the Zr oxide film was 36.5
(.ANG.), the in-plane uniformly was .+-.7.3 (%), and the
inter-wafer uniformly was .+-.1.4 (%).
PREFERABLE ASPECTS OF THE INVENTION
[0133] Preferable aspects of the present invention will now be
supplementary described.
[0134] According to the first aspect of the present invention,
there is provided a substrate processing apparatus including:
[0135] a processing chamber for storing and processing substrates
stacked in multiple stages in horizontal posture;
[0136] a processing gas supply unit for supplying at least one type
of processing gas to the inside of the processing chamber;
[0137] an inactive gas supply unit for supplying an inactive gas to
the inside of the processing chamber; and
[0138] an exhaust unit for exhausting an atmosphere of the inside
of the processing chamber,
[0139] wherein
[0140] the processing gas supply unit has at least one processing
gas supply nozzle which extends running along an inner wall of the
processing chamber in the stacking direction of the substrates and
which supplies the processing gas to the inside of the processing
chamber, and
[0141] the inactive gas supply unit has a pair of inactive gas
supply nozzles which are provided so as to extend running along the
inner wall of the processing chamber in the stacking direction of
the substrates and so as to sandwich the processing gas supply
nozzle from both sides thereof along the circumferential direction
of the substrates, and which supply the inactive gas to the inside
of the processing chamber.
[0142] According to the second aspect of the present invention,
there is provided a substrate processing apparatus according to the
first aspect, wherein
[0143] the pair of the inactive gas supply nozzles have at least
one inactive gas ejection port for supplying the inactive gas
toward the center direction of the substrate.
[0144] According to the third aspect of the present invention,
there is provided a substrate processing apparatus according to the
first or second aspect, further including:
[0145] a control section for controlling at least the processing
gas supply unit and the inactive gas supply unit,
[0146] wherein
[0147] the control section controls the processing gas supply unit
and the inactive gas supply unit such that a supply flow quantity
of the inactive gas is greater than a supply flow quantity of the
processing gas.
[0148] According to the fourth aspect of the present invention,
there is provided a substrate processing apparatus according to the
first aspect, further including:
[0149] a heating unit for heating an atmosphere in the processing
chamber; and a control section for controlling at least the heating
unit, wherein the control section controls the heating unit such
that a temperature of the atmosphere in the processing chamber
becomes a certain processing temperature.
[0150] According to the fifth aspect of the present invention,
there is provided a substrate processing apparatus according to the
fourth aspect, wherein
[0151] a thermal decomposition temperature of the processing gas is
lower than the processing temperature.
[0152] According to the sixth aspect of the present invention,
there is provided a substrate processing apparatus according to the
fourth or fifth aspect, further including:
[0153] a control section for controlling at least the processing
gas supply unit and the inactive gas supply unit,
[0154] wherein
[0155] the control section
[0156] controls the processing gas supply unit and the inactive gas
supply unit such that a supply flow quantity of the inactive gas is
greater than a supply flow quantity of the processing gas.
[0157] According to the seventh aspect of the present invention,
there is provided a substrate processing apparatus including:
[0158] an outer tube;
[0159] an inner tube which is installed inside the outer tube with
at least the lower end thereof being opened, and which stores the
substrates stacked in multiple stages in horizontal posture;
[0160] a processing gas supply unit for supplying at least one type
of processing gas to the inside of the inner tube;
[0161] an inactive gas supply unit for supplying an inactive gas to
the inside of the inner tube; and
[0162] an exhaust hole provided at a position opposing the
processing gas supply nozzle on the side wall of the inner tube,
[0163] wherein
[0164] the processing gas supply unit has at least one processing
gas supply nozzle which is vertically installed inside the inner
tube so as to extend in the stacking direction of the substrates
and which has at least one processing gas ejection port for
supplying the processing gas, and
[0165] the inactive gas supply unit
[0166] has a pair of inactive gas supply nozzles which are provided
so as to be vertically installed, inside the inner tube, extending
in the stacking direction of the substrates and so as to sandwich
the processing gas supply nozzle from both sides thereof along the
circumferential direction of the substrates and which have at least
one inactive gas ejection port for supplying the inactive gas.
[0167] According to the eighth aspect of the present invention,
there is provided a substrate processing apparatus according to the
seventh aspect, wherein
[0168] a preliminary chamber is formed projecting outward in the
radial direction in the inner tube,
[0169] the processing gas supply nozzle is provided in the
preliminary chamber, and
[0170] the processing gas ejection port is located outward in the
radial direction with respect to an inner peripheral surface of the
inner tube.
[0171] According to the ninth aspect of the present invention,
there is provided a substrate processing apparatus according to the
seventh aspect, wherein
[0172] a preliminary chamber is formed projecting outward in the
radial direction in the inner tube,
[0173] the pair of the inactive gas supply nozzles are provided in
the preliminary chamber, and
[0174] the inactive gas ejection port is located outward in the
radial direction with respect to an inner peripheral surface of the
inner tube.
[0175] According to the tenth aspect of the present invention,
there is provided a substrate processing apparatus according to any
one of the seventh to ninth aspects, wherein
[0176] a first straight line connecting the processing gas supply
nozzle and the exhaust hole is configured to pass the vicinity of
the center of the substrates.
[0177] According to the eleventh aspect of the present invention,
there is provided a substrate processing apparatus according to the
tenth aspect, wherein
[0178] the processing gas ejection port is configured to be opened
substantially parallel to the first straight line.
[0179] According to the twelfth aspect of the present invention,
there is provided a substrate processing apparatus according to the
tenth aspect, wherein
[0180] second and third straight lines connecting the pair of the
inactive gas supply nozzles and the exhaust hole, respectively, are
configured to sandwich the first straight line from both sides
thereof, respectively.
[0181] According to the thirteenth aspect of the present invention,
there is provided a substrate processing apparatus according to the
twelfth aspect, wherein
[0182] the inactive gas ejection port is configured to be opened
substantially parallel to the second and third straight lines.
[0183] According to the fourteenth aspect of the present invention,
there is provided a substrate processing apparatus according to the
twelfth aspect, wherein
[0184] the inactive gas ejection port is configured to be opened in
the outward orientation with respect to the second and third
straight lines.
[0185] According to the fifteenth aspect of the present invention,
there is provided a substrate processing apparatus according to any
one of the seventh to fourteenth aspects, further including:
[0186] a heating unit for heating an atmosphere in the processing
chamber;
[0187] a control section for controlling at least the processing
gas supply unit,
[0188] wherein
[0189] the control section
[0190] controls the heating unit such that a temperature of the
atmosphere in the processing chamber becomes a certain processing
temperature.
[0191] According to the sixteenth aspect of the present invention,
there is provided a substrate processing apparatus according to the
fifteenth aspect, wherein
[0192] a thermal decomposition temperature of the processing gas is
lower than the processing temperature.
[0193] According to the seventeenth aspect of the present
invention, there is provided a substrate processing apparatus
according to any one of the seventh to fourteenth aspects, further
including:
[0194] a control section for controlling at least the processing
gas supply unit and the inactive gas supply unit,
[0195] wherein
[0196] the control section
[0197] controls the processing gas supply unit and the inactive gas
supply unit such that a supply flow quantity of the inactive gas is
greater than a supply flow quantity of the processing gas.
[0198] According to the eighteenth aspect of the present invention,
there is provided a substrate processing apparatus according to the
fifteenth or sixteenth aspect, wherein
[0199] the control section
[0200] controls the processing gas supply unit and the inactive gas
supply unit such that a supply flow quantity of the inactive gas is
greater than a supply flow quantity of the processing gas.
[0201] According to the nineteenth aspect of the present invention,
there is provided a substrate processing apparatus according to the
seventh aspect, wherein
[0202] the pair of the inactive gas supply nozzles has at least one
inactive gas ejection port for supplying the inactive gas toward
the center direction of the substrate.
[0203] According to the twentieth aspect of the present invention,
there is provided a substrate processing apparatus which repeatedly
supplies two or more types of processing gases alternately to a
surface of a substrate for a certain number of times, in a manner
so as not to mix the processing gases, and which forms a thin film
on the surface of the substrate, the substrate processing apparatus
including:
[0204] a processing chamber for storing and processing substrates
stacked in multiple stages in horizontal posture;
[0205] a processing gas supply unit for supplying two or more types
of the processing gases to the inside of the processing
chamber;
[0206] an inactive gas supply unit for supplying an inactive gas to
the inside of the processing chamber; and
[0207] an exhaust unit for exhausting an atmosphere of the inside
of the processing chamber,
[0208] wherein
[0209] the processing gas supply unit has at least two processing
gas supply nozzles which extend running along an inner wall of the
processing chamber in the stacking direction of the substrates and
supply the processing gas to the inside of the processing chamber,
and
[0210] the inactive gas supply unit has a pair of inactive gas
supply nozzles which are provided so as to extend running along the
inner wall of the processing chamber in the stacking direction of
the substrates and so as to sandwich at least one processing gas
supply nozzle of the at least two processing gas supply nozzles
from both sides thereof, along the circumferential direction of the
substrates, and which supply the inactive gas to the inside of the
processing chamber.
[0211] According to the twenty-first aspect of the present
invention, there is provided a substrate processing apparatus
according to the twentieth aspect, wherein
[0212] the at least one processing gas supply nozzle sandwiched
from both sides thereof by the pair of the inactive gas supply
nozzles supplies the processing gas which affects the in-plane
uniformity of thin film thickness.
[0213] According to the twenty-second aspect of the present
invention, there is provided a substrate processing apparatus
according to the twentieth aspect, wherein
[0214] the processing gas supply unit has:
[0215] a first processing gas supply nozzle for supplying a first
processing gas which affects the in-plane uniformity of thin film
thickness, and
[0216] a second processing gas supply nozzle for supplying a second
processing gas which does not affect the in-plane uniformity of
thin film thickness,
[0217] and
[0218] the first processing gas supply nozzle is sandwiched from
both sides thereof by the pair of the inactive gas supply nozzles
along the circumferential direction of the substrates.
[0219] According to the twenty-third aspect of the present
invention, there is provided a substrate processing apparatus,
including:
[0220] a processing chamber for storing and processing substrates
stacked in multiple stages in horizontal posture;
[0221] at least one processing gas supply nozzle which extends
running along an inner wall of the processing chamber in the
stacking direction of the substrates and supplies a processing gas
to the inside of the processing chamber;
[0222] a pair of inactive gas supply nozzles which extend running
along the inner wall of the processing chamber in the stacking
direction of the substrates and which supply an inactive gas to the
inside of the processing chamber; and
[0223] an exhaust line for exhausting the inside of the processing
chamber,
[0224] wherein
[0225] the pair of the inactive gas supply nozzles are arranged
such that a flow passage of a gas flow of the processing gas
supplied from the processing gas supply nozzle is restricted by a
gas flow of the inactive gas supplied from the inactive gas supply
nozzle.
[0226] According to the twenty-fourth aspect of the present
invention, there is provided a substrate processing apparatus,
including:
[0227] a processing chamber for storing and processing substrates
stacked in multiple stages in horizontal posture;
[0228] at least one processing gas supply nozzle which extends
running along an inner wall of the processing chamber in the
stacking direction of the substrates and which supplies a
processing gas to the inside of the processing chamber;
[0229] a pair of the inactive gas supply nozzles which extend
running along the inner wall of the processing chamber in the
stacking direction of the substrates and which supply the inactive
gas to the inside of the processing chamber; and
[0230] an exhaust line for exhausting the inside of the processing
chamber,
[0231] wherein
[0232] the pair of the inactive gas supply nozzles supply the
inactive gas to a clearance between the inner wall of the
processing chamber and the substrate.
[0233] According to the twenty-fifth aspect of the present
invention, there is provided a method for manufacturing a
semiconductor device, including the steps of:
[0234] loading substrates stacked in multiple stages in horizontal
posture to the inside of the processing chamber;
[0235] processing the substrates, by supplying a processing gas, to
the inside of the processing chamber, from at least one processing
gas supply nozzle which extends running along an inner wall of the
processing chamber in the stacking direction of the substrates, and
by supplying an inactive gas, to the inside of the processing
chamber, from a pair of inactive gas supply nozzles, which are
provided so as to extend running along the inner wall of the
processing chamber in the stacking direction of the substrates and
so as to sandwich the processing gas supply nozzle from both sides
thereof along the circumferential direction of the substrates;
and
[0236] unloading the processed substrates from the processing
chamber.
[0237] According to the twenty-sixth aspect of the present
invention, there is provided a method for manufacturing a
semiconductor device according to the twenty-fifth aspect,
wherein
[0238] In the step of processing the substrates, a flow quantity of
the inactive gas supplied from each of the pair of the inactive gas
supply nozzles is set to be equal to or greater than a flow
quantity of the processing gas supplied from the processing gas
supply nozzle.
[0239] According to the twenty-seventh aspect of the present
invention, there is provided a method for manufacturing a
semiconductor device which repeatedly supplies two or more types of
processing gases alternately to a surface of a substrate for a
certain number of times, in a manner so as not to mix the
processing gases, and which forms a thin film on the surface of the
substrate, the method including the steps of:
[0240] loading substrates stacked in multiple stages in horizontal
posture to the inside of the processing chamber;
[0241] a first gas supply step for supplying a first processing gas
to the inside of the processing chamber;
[0242] a first exhaust step for exhausting the atmosphere in the
processing chamber;
[0243] a second gas supply step for supplying a second processing
gas to the inside of the processing chamber; and
[0244] a second exhaust step for exhausting the atmosphere in the
processing chamber,
[0245] wherein
[0246] in at least one step of the first gas supply step and the
second gas supply step, an inactive gas is supplied so as to
sandwich at least one of a gas flow of the first processing gas or
a gas flow of the second processing gas from both sides
thereof.
[0247] According to the twenty-eighth aspect of the present
invention, there is provided a substrate processing apparatus,
including:
[0248] a processing chamber for storing and processing substrates
stacked in multiple stages in horizontal posture;
[0249] at least one processing gas supply nozzle which extends
running along an inner wall of the processing chamber in the
stacking direction of the substrates and supplies a processing gas
to the inside of the processing chamber;
[0250] a pair of the inactive gas supply nozzles which are provided
so as to extend running along the inner wall of the processing
chamber in the stacking direction of the substrates and so as to
sandwich the processing gas supply nozzle from both sides thereof
along the circumferential direction of the substrates and which
supply the inactive gas to the inside of the processing
chamber;
[0251] an inactive gas ejection port provided in the inactive gas
supply nozzle; and
[0252] an exhaust line for exhausting the inside of the processing
chamber,
[0253] wherein
[0254] the inactive gas ejection port is opened so as to inject the
inactive gas to a space between the inner wall of the processing
chamber and the outer periphery section of the substrate.
[0255] According to the twenty-ninth aspect of the present
invention, there is provided a substrate processing apparatus
according to any one of the first to twenty-eighth aspects, further
including:
[0256] a pair of straightening vanes outside of the inactive gas
nozzles, respectively, which are located on the inner side of the
processing chamber with respect to the inactive gas ejection
port.
[0257] According to the thirtieth aspect of the present invention,
there is provided a substrate processing apparatus according to the
twenty-eighth aspect, further including:
[0258] a pair of straightening vanes each of which extends between
the inactive gas supply nozzle and the substrate in the vertical
direction and located substantially parallel to the orientation of
the inactive gas ejection port.
[0259] According to the thirty-first aspect of the present
invention, there is provided a substrate processing apparatus
according to the twenty-ninth or thirtieth aspect, wherein
[0260] each straightening vane is mounted on the inactive gas
supply nozzle.
[0261] According to the thirty-second aspect of the present
invention, there is provided a substrate processing apparatus
according to the twenty-ninth or thirtieth aspect, wherein
[0262] each straightening vane is mounted on the inner wall of the
processing chamber.
* * * * *