U.S. patent application number 15/696890 was filed with the patent office on 2017-12-21 for apparatus and method.
This patent application is currently assigned to BENEQ OY. The applicant listed for this patent is BENEQ OY. Invention is credited to Sami SNECK, Pekka SOININEN.
Application Number | 20170362708 15/696890 |
Document ID | / |
Family ID | 42669405 |
Filed Date | 2017-12-21 |
United States Patent
Application |
20170362708 |
Kind Code |
A1 |
SOININEN; Pekka ; et
al. |
December 21, 2017 |
APPARATUS AND METHOD
Abstract
An apparatus and a method for processing a surface of a
substrate exposes the surface of the substrate to alternating
surface reactions of at least a first starting material and a
second starting material according to the principles of atomic
layer deposition method. A first starting material is fed on the
surface of the substrate locally by a source by moving the source
in relation to the substrate, and the surface of the substrate
processed with the first starting material is exposed to a second
starting material present in the atmosphere surrounding the
source.
Inventors: |
SOININEN; Pekka; (Helsinki,
FI) ; SNECK; Sami; (Vantaa, FI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BENEQ OY |
Vantaa |
|
FI |
|
|
Assignee: |
BENEQ OY
Vantaa
FI
|
Family ID: |
42669405 |
Appl. No.: |
15/696890 |
Filed: |
September 6, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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13816870 |
Mar 14, 2013 |
9783887 |
|
|
PCT/FI2011/050752 |
Aug 30, 2011 |
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15696890 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C23C 16/45551 20130101;
C23C 16/45544 20130101 |
International
Class: |
C23C 16/455 20060101
C23C016/455 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 30, 2010 |
FI |
20105901 |
Claims
1. An apparatus for processing a surface of a substrate by exposing
the surface of the substrate to alternating surface reactions of at
least a first starting material and a second starting material
according to the principles of atomic layer deposition method,
wherein the apparatus comprises one or more sources for feeding the
first starting material locally on the surface of the substrate and
feeding means for feeding second starting material to atmosphere
surrounding the one or more sources, and that the one or more
sources are positioned in the atmosphere comprising the second
starting material.
2. The apparatus according to claim 1, wherein the source comprises
one or more starting material zone(s), through which the first
starting material is fed locally on the surface of the
substrate.
3. The apparatus according to claim 1, wherein the source is
adapted to be movable on the surface of the substrate or in the
proximity thereof in relation to the substrate.
4. The apparatus according to claim 1, wherein the source is
adapted to be rotated in relation to the surface of the
substrate.
5. The apparatus according to claim 4, wherein the source comprises
a rotatable starting material feeding member, which comprises one
or more starting material zone(s) for feeding first starting
material on the surface of the substrate.
6. The apparatus according to claim 5, wherein the starting
material feeding member is adapted to be rotatable about the first
rotation axis and to feed the first starting material substantially
in the direction of the first rotation axis via the starting
material zone.
7. The apparatus according to claim 5, wherein the starting
material feeding member is adapted to be rotatable about the second
rotation axis and to feed the first starting material substantially
transversely, radially or perpendicularly in relation to the second
rotation axis via the starting material zone.
8. The apparatus according to claim 1, wherein the substrate is
adapted to be movable in relation to the source.
9. The apparatus according to claim 3, wherein the source or the
gas feeding member is adapted to be movable substantially with a
reciprocating movement directed in accordance with the surface of
the substrate on the surface of the substrate or in the proximity
of the surface.
10. The apparatus according to claim 1, wherein the source for
conducting at least one flushing agent to the surface of the
substrate for flushing of the surface of the substrate.
11. The apparatus according to claim wherein the source comprises
at least one suction zone for drawing the first starting material
or the flushing agent fed on the surface of the substrate or for
providing vacuum between the source and the surface of the
substrate.
12. The apparatus according to claim 1, wherein the source
comprises two or more starting material zones, which are separated
from each other by a slit or space in flow connection to the
surrounding atmosphere for exposing the surface of the substrate to
the second starting material between the starting material
zones.
13. The apparatus according to claim 5, wherein the source
comprises two or more starting material feeding members, which are
separated from each other by a slit or space opening to the
surrounding atmosphere for exposing the surface of the substrate to
the second starting material between the starting material feeding
members.
14. The apparatus according to claim 1, wherein the apparatus
comprises two or more sources, which are separated from each other
by a slit or space opening to the surrounding atmosphere for
exposing the surface of the substrate to the second starting
material between the sources.
15. The apparatus according to claim 1, wherein the apparatus
comprises a deposition chamber, wherein the source is positioned
and into which deposition chamber the atmosphere is provided.
16. The apparatus according to claim 1, wherein the apparatus is
adapted to function in normal atmospheric pressure or in
vacuum.
17. The apparatus according to claim 1, wherein the first or the
second starting material is plasma or radical or is adapted to
provide a sparkle.
18. The apparatus according to claim 1, wherein the second starting
material is reactive or non reactive.
19. The apparatus according to claim 1, wherein the second starting
material is air, water vapor or oxygen.
Description
BACKGROUND OF THE INVENTION
[0001] The invention relates to an apparatus and a method for
processing a surface of a substrate by exposing the surface of the
substrate to alternating surface reactions of starting materials.
Specifically, the present invention relates to an apparatus for
processing a surface of a substrate by exposing the surface of the
substrate to alternating surface reactions of at least a first
starting material and a second starting material according to the
principles of atomic layer deposition method. Particularly, the
present invention relates also to a method for processing a surface
of a substrate by exposing the surface of the substrate to
alternating surface reactions of at least a first starting material
and a second starting material according to the principles of
atomic layer deposition method.
[0002] Atomic Layer Deposition ALD method is based on deposition
controlled by a surface, wherein the starting materials are
conducted inside an ALD reactor onto the surface of the substrate
one by one non-simultaneously and mutually separated. Traditionally
starting material is brought onto the surface of the substrate in a
sufficient amount so that all available binding sites of the
surface will be in use. After each pulse of starting material the
substrate will be flushed with inert gas so as to remove the excess
of starting material steam in order to avoid the deposition from
occurring in the gaseous phase. Then a chemisorbed monolayer of the
reaction product of one starting material will remain on the
surface. This layer reacts with the next starting material forming
a partial monolayer of desired material. The reaction having
occurred completely enough an excess amount of this second starting
material steam will be flushed with inert gas, so the deposition is
based on saturated surface reactions, i.e. the surface controls the
deposition. According to a known technique the aforementioned ALD
method will be carried in an ALD reactor in which the substrate to
be processed is positioned.
[0003] One problem in the arrangement according to above described
prior art technique is that with ALD reactors it is not possible to
process pieces which are so large that they do not fit inside an
ALD reactor. This limits considerably the use of the ALD method in
many applications. Another problem is that the ALD method is used
according to a known technique with vacuum. When depositing for
example inner surfaces of containers the container itself may form
an ALD reactor in which the vacuum is provided. However, wall
thickness of such containers is often not sufficient, and the
container may not withstand the necessary vacuum and the container
may collapse. Moreover feeding of starting materials successively
into large chambers may be difficult and time consuming, since
filling and emptying of large chamber is slow. Moreover all the
surfaces of the substrate placed in the chamber will be exposed to
surface reactions, whereupon it is not possible to expose only part
of the surface of the substrate to surface reactions without
mounting on the surface of the substrate masks which cover part of
the surface of the substrate. However placing of such masks is
often slow and complicated.
BRIEF DESCRIPTION OF THE INVENTION
[0004] An object of the invention is thus to develop an apparatus
and a method which solve the aforementioned problems. The object of
the invention is solved by an apparatus that comprises one or more
sources for feeding first starting material locally on a surface of
a substrate, and in that the source is positioned in an atmosphere
which comprises second starting material. The object of the
invention is further achieved with a method that includes feeding
on the surface of the substrate locally a first starting material
by means of the source by moving the source in relation to the
substrate and exposing the surface of the substrate processed with
the first starting material to a second starting material present
in the atmosphere surrounding the source.
[0005] The preferred embodiments of the invention are object of the
dependent claims.
[0006] The invention is based on providing an apparatus, which
comprises one or more sources for feeding first starting material
locally on the surface of the substrate. The source may for example
be a nozzle, nozzle head or like, which is adapted to feed a first
starting material on the surface of the substrate. The first
starting material reacts with the surface of the substrate forming
a monolayer on the surface of the substrate. The source is provided
movable in relation to the surface of the substrate so that by the
source it is possible to sweep over the surface of the substrate or
part of the surface by exposing this surface of the substrate left
under the sweeping to a first starting material. The relative
movement of the source and the substrate may be provided by moving
uniquely the source or by moving uniquely the substrate or by
moving both the substrate and the source relative to each other.
According to the present invention the substrate and the source are
positioned in an atmosphere which comprises second starting
material. In other words the apparatus of the invention comprises
feeding means for feeding second starting material to the
atmosphere surrounding the source. Thus, when the surface of the
substrate is exposed locally by means of the source to a first
starting material, it will be exposed after having been swept by
the source to a second starting material, which is present in the
atmosphere surrounding the substrate. The second starting material
reacts with the first starting material forming a monolayer on the
surface of the substrate. This monolayer formed by the second
starting material in turn reacts with the first starting material
fed from the source upon next sweeping. Thus, the surface of the
substrate may be processed locally by means of the source, when
surface reactions occur on the surface of the substrate uniquely at
the location which was swept by the source in order to expose the
surface of the substrate to the first starting material.
[0007] As described before, the number of sweeps performed with the
source may serve to determine the desired number of deposition
layers and thus for example the thickness of the desired
deposition, because as a result of each sweeping there is formed
one monolayer of first and second starting material on the surface
of the substrate. Processing of a surface means in this application
generally depositing a surface, alloying a surface layer and/or
some other corresponding procedure for processing a surface or a
surface layer. On the surface of the substrate means in this
context both the external surface and the internal surfaces of a
porous substrate, which are provided by the porosity.
[0008] An advantage of the method and the apparatus of the
invention is that it permits to use the ALD method also for
processing surfaces of large pieces, which has not been possible
earlier because of the dimensional limitation provided by ALD
reactors. Moreover the present invention allows for local
processing of such large pieces or surfaces, when processing of the
whole surface is not desired or preferred, which has not been
possible with prior art ALD reactors. Further, in the solution
according to the present invention there is no need to use vacuum
at all, or vacuum may be generated only at the location of the
nozzle surface, whereupon thin-walled pieces are not exposed to
vacuum, which might brake up the wall or collapse a thin-walled
container. Moreover the present invention allows to process quickly
large pieces with the ALD method and to use efficiently starting
materials and possible flushing agents by minimizing the waste
amount produced by the excess thereof.
BRIEF DESCRIPTION OF FIGURES
[0009] The invention will now be described in further detail in
connection with preferred embodiments, with reference to the
accompanying drawings, in which:
[0010] FIG. 1 shows schematically an embodiment of the apparatus
according to the present invention;
[0011] FIGS. 2A and 2B show schematically another embodiment of he
apparatus according to the present invention;
[0012] FIG. 3 shows schematically another embodiment of the
apparatus according to the present invention;
[0013] FIG. 4 shows schematically still another embodiment of the
apparatus according to the present invention; and
[0014] FIG. 5 shows schematically a side view of the apparatus
according to FIG. 4.
DETAILED DESCRIPTION OF THE INVENTION
[0015] Referring to FIG. 1 a first embodiment of the apparatus of
the present invention is shown. According to FIG. 1 the apparatus
comprises a source 6, which may be positioned on the surface 4 of
the substrate 2 to be processed. The source 6 comprises a nozzle
surface, which is placed against the surface 4 of the substrate 2
to be processed or on the surface 4 within a distance from the
surface 4 so that the nozzle surface will cover part of the surface
4 of the substrate 2. Thus, the nozzle surface means in this
context the surface of the source 6, which is placed against the
surface 4 of the substrate 2 or on the surface 4. By means of the
source a first starting material A is conducted via nozzle surface
on the surface 4 of the substrate 2 at the region covered by the
nozzle surface so that at this region covered by the nozzle surface
the surface 4 of the substrate 2 may be exposed to a first starting
material A. The first starting material A may be fed together with
a carrier gas, which carder gas may be an inert gas, which does not
take part in the surface reactions on the surface 4 of the
substrate 2. According to FIG. 1, the source 6 comprises a starting
material space 13, into which the first starting material A may be
fed by means of gas feeding means 14, which are in flow connection
to the starting material space 13. Gas feeding means 14 may
comprise any connections, tubings, starting material inserts and
similar means and parts which are needed in order to produce and
feed the first starting material A into the starting material space
13. In the embodiment of FIG. 1 a gas delivery device 16, such as
an aperture plate or similar, is arranged in the upper part of the
starting material space 13 in order to deliver uniformly the first
starting material A originating from gas feeding means 14 into the
starting material space 3. The starting material space 13 comprises
an open wall or area, which opens to the nozzle surface forming a
starting material zone 10, from which the first starting material A
fed into the starting material space 13 will gain connection with
the surface 4 of the substrate 2. In other words, according to the
present invention first starting material A is able to discharge
via the starting material zone 10 on the area of the surface 4 of
the substrate 2 which is covered by the nozzle surface and
particularly below the starting material zone 10, the source 6
being placed against the surface 4 of the substrate 2 or on the
surface 4. The starting material space 13 of the source 6 thus
forms an ALD reaction chamber with the part of the surface 4 of the
substrate 2 on which the source 6 is located. Then deposition of
material according to the ALD method may occur at this part of the
surface 4 of the substrate 2 covered by the starting material zone
10 of the source 6 under the influence of the first starting
material A. The nozzle surface of the source 6 may further be
provided with bristles 30, which surround the starting material
zone 10 and protrude outwardly from the nozzle surface so that a
slit will remain between the nozzle surface and the surface 4 of
the substrate 2. This slit together with the bristles 30 allows the
excess starting material fed into the starting material space 13 to
exit from the starting material space 13 and at the same time the
bristles allow the source 6 to be used also on surfaces thereof
which comprise irregularities which are small or lower than the
height of the bristles 30. An underdosage or quasi underdosage may
also be fed into the starting material space 13, whereupon
substantially all of the first starting material A fed reacts with
the surface 4 of the substrate 2. When using an underdosage no
additional first starting material A is able to flow outside the
starting material space 13.
[0016] According to the invention the source 6 is made movable so
that it may be moved along the surface 4 of the substrate 2, the
nozzle surface being against the surface 4 of the substrate 2 or on
the surface within a distance therefrom. In other words, the source
6 is moved relative to the substrate 2. Alternatively the source 6
may be stationary, and the substrate 2, like the material web, is
moved relative to the source 6, the source 6 being placed against
or over the surface 4 of the substrate. Also both the substrate 2
and the source 6 may be moved in order to obtain a relative
movement. In yet another embodiment the source 6 may be placed
against or over the surface 4 of the substrate 2, lifted away from
the surface 4 and transferred to the next place and repositioned
against or over the surface 4 of the substrate 2. Then the source 6
is not moved along the surface of the substrate but is placed at
the desired location, removed and placed to the next location on
the substrate 2.
[0017] Using the source 6 according to FIG. 1 it is possible to
process the surface 4 of the substrate 2 according to the ALD
method by bringing by means of gas feeding means 14 a first
starting material A into the starting material space 13, the
surface 4 of the substrate 2 being exposed to a surface reaction
provided by the first starting material B. By feeding the first
starting material A at an underdosage relative to the capacity of
the surface 4 of the substrate 2 to bind starting materials,
substantially all of the fed first starting material A will bind
onto the surface 3 of the substrate 2, so that there is no need to
flush the surface separately. In case of overdosage the first
starting material A in excess will exit the nozzle surface through
bristles 30 or the slit between the nozzle surface and the surface
4 of the substrate 2. According to FIG. 1 the source 6 is
positioned in a space the atmosphere 1 of which comprises a second
starting material B. This space which has atmosphere 1, may for
example be a separate chamber or a room space or some other
corresponding space in which atmosphere 1, which contains the
second starting material B, may be maintained. The relative
movement of the source 6 on the surface 4 of the substrate 2
exposes the surface 4 to the first starting material A as the
nozzle sweeps over the surface 4 and the surface 4 is exposed after
sweeping to the second starting material B present in the
atmosphere 1 of the space, when the source no more covers the
location of the surface 4 of the substrate 2 which was swept by the
source 6. Thus one sweep of source 6 over the surface 4 of the
substrate 2 provides on the surface 4 one deposition layer of first
and second starting material A, B in order to perform one complete
ALD cycle. By feeding into the starting material space 13 an
underdosage of first starting material A relative to the capacity
of the surface 4 to bind starting material A the need of flushing
the surface 4 may be eliminated, because all of the starting
material A entering the surface via the starting material zone 10
binds to the surface 4. At the same time the carrying gas to be fed
with the first starting material A flows through the bristles away
from the nozzle surface by blowing away the second starting
material B present in the atmosphere 1 preventing it from entering
below the nozzle surface. The movement rate of the source 6
relative to the substrate 2 and the feeding rate of the first
starting material A into the starting material space 13 may be
dimensioned so that a desired underdosage state or other dosage
state is obtained. Thus, by means of a reciprocating relative
movement of the source 6 on the surface 4 of the substrate 2 a
desired amount of deposition layers may be obtained, with each
sweeping of the nozzle 6 one deposition layer is obtained. In FIG.
1, the reciprocating movement of the nozzle is illustrated by arrow
M. The apparatus may also comprise two or more sources 6, which may
be positioned for example on one another so that the substrate 2
may pass below these sources and be exposed to the second starting
material B present in the atmosphere 1 between the sources.
[0018] In FIGS. 2A and 2B there is shown a particular embodiment of
the lamellar structured nozzle surface of the source 6. This source
6 according to FIGS. 2A and 2B corresponds with its operation
principles and applications substantially to the source of FIG. 1,
but in this source 6 according to FIGS. 2A and 2B there is a
lamellar structure for feeding flushing agents as well as a suction
for extracting the flushing agent and the starting materials. In
the embodiment of FIGS. 2A and 2B the nozzle surface contains a
starting material zone 10, through which the first starting
material A is fed on the surface 4 of the substrate 2. In FIG. 2A
there is shown a plan view of the nozzle surface, which comprises
in the middle a starting material zone 10, to which first starting
material A is brought by means of gas feeding means 14. Starting
material zone 10 is surrounded by suction zone 24, on which suction
or vacuum is provided by means of suction means or vacuum means 27,
which are in flow connection to the suction space 19. The suction
zone 24 in turn is surrounded by flushing agent zone 22, to which
flushing agent is fed by means of flushing agent delivery means 21.
With this solution it is possible to obtain around the reaction
space defined by the starting material zone 10 zones of inertgas
valving type, which further allow using the first starting material
A at an overdosage. In FIG. 2B there is shown schematically in side
view the solution according to FIG. 2A. Thus, the first starting
material A fed into the starting material space 13 by means of gas
feeding means 14 flows via the starting material zone 10 on the
surface 4 of the substrate 2, wherein the excess first starting
material A and/or carrying gas fed into the starting material space
will be drawn from the slit between nozzle surface and the surface
4 of the substrate 2 into the suction space 19 and away from the
surface 2 of the substrate 2. At the same time flushing agent is
fed by means of flushing agent feeding means 21 into the flushing
agent space 23, which flushing agent flows via the flushing agent
zone 22 on the surface of the substrate and is further absorbed via
the suction zone 24 into the suction space 19. By dimensioning
suitably the feed pressure of the flushing agent, the efficiency of
the feed pressure of the first starting material A as well as the
surface areas of the flowing channels thereof, a source 6 may be
achieved, inside which a good vacuum is present and when at the
same time it however neutralizes by means of the feeding rate of
the first starting material A and the flushing agent the suction
force generated by vacuum, wherein the source 6 may be moved easily
on the surface 4 of the substrate 2. Also in this embodiment the
nozzle surface may be provided with bristles, which may be
positioned around any one of the zones 10, 22, 24 and when needed
around more or all of these zones 10, 22, 24. Further it is to be
noted that two or more of the lamellar structures according to
FIGS. 2A and 2B may be provided on a nozzle surface, and between
these lamellar structures there may be a slit or gap or
corresponding space, which is in flow connection to the atmosphere
1 in order to expose the surface 4 of the substrate 2 between the
lamellar structures to starting material B. This source according
to FIGS. 2A and 2B may be used in the same manner as the source
according to FIG. 1 by providing a relative movement between the
source 6 and the substrate 2.
[0019] According to the invention the nozzle surface is provided so
that the source 6 comprises a starting material space 13, which is
in flow connection to the gas feeding means 14, which starting
material space 13 comprises a region opening to the nozzle surface
of the source 6, which forms the starting material zone 10, through
which the first material A is able to flow to the surface 4 of the
substrate 2, the nozzle surface being placed against and on the
surface 4 of the substrate 2 at a distance from the surface 4.
Correspondingly the flushing agent space 23 is in flow connection
to the flushing agent delivery means 21, which flushing agent space
23 comprises an area opening to the nozzle surface of the source 6,
which forms the flushing agent zone 22, through which the flushing
agent is able to flow to the surface 4 of the substrate 2, the
nozzle surface being placed against or over the surface 4 of the
surface 2. The suction space 19 is in flow connection to the
suction means 27, which suction space 19 comprises an area opening
to the nozzle surface, which area forms the suction zone 24,
through which first starting material A and/or flushing agent may
be drawn the nozzle surface being placed against or over the
surface 4 of the substrate 2, and/or the suction space 19, which
provides vacuum between the nozzle surface of the source 6 and the
surface 4 of the substrate 2.
[0020] Although the lamellar solution of FIGS. 2A and 2B is shown
as nested zones it may however be provided as successive zones. In
other words the source 6 may comprise on the nozzle surface thereof
in order to flush the surface 4 of the substrate 2 at least one
flushing agent zone 22 for conducting flushing agent to the surface
4 of the substrate 2. The flushing agent zone 22 may further be
arranged successively in respect to the moving direction of the
substrate 2 or the source 6 with the starting material zone 10
and/or in the moving direction of the source 6 in front or rear
side of the starting material zone 10. Likewise the source 6 may
comprise in addition on the nozzle surface thereof at least one
suction zone 24 for drawing the first starting material A and/or
the flushing agent fed on the surface 1 of the substrate 2 and/or
for providing vacuum between the nozzle surface of the source 6 and
the surface 4 of the substrate 2. The suction zone 24 may be
arranged successively in relation to the moving direction of the
substrate 2 and the nozzle 6 with the starting material zone 10 in
the same manner as was described in connection with the flushing
agent zone 22, i.e. at the front or rear side or both sides of the
starting material zone 10. Preferably the suction zone 24 is
positioned between the starting material zone 10 flushing agent
zone 22.
[0021] In FIG. 3 there is shown a particular embodiment of the
present invention, in which three similar sources 7 are positioned
over a substrate 2 moving in the direction of arrow N, for example
a material web, so that the nozzle surface of the source 7 is
against or over the surface 4 of the substrate 2 at a distance from
the surface 4. The sources 7 have in this embodiment a starting
material feeding member 3 with a round nozzle surface, which
starting material feeding member 3 is adapted to rotate about the
rotation axis 15 or the center point thereof as described with the
arrow P. The nozzle surface comprises a starting material zone 11,
through which first starting material A may be fed on the surface 4
of the substrate 2 in the same manner as in the embodiment of FIG.
1. The sources 7 are again positioned in the atmosphere 1, which
contains second starting material B. The sources 7 feed on the
surface 4 of the substrate a first starting material A and the
atmosphere 1 has a second starting material B, wherein the surface
4 would be exposed alternatively to starting materials A and B. The
number of deposition layers available to the surface 4 of the web 2
and thus the thickness of the deposition layers may be controlled
by means of the rotation speed of the nozzles 6 and the moving rate
of the web. The sources 7 and the starting material feeding members
3 may also be provided with slits or corresponding zones (not
shown), which are in flow connection to the atmosphere 1 so that
the surface 4 of the substrate 2 may be exposed to surface
reactions of the second starting material B present in the
atmosphere 1, the source rotating about the first rotation axis 15.
These slits may be provided for example in the gaps of starting
material zones 11. The first rotation axis 15 extends in this
embodiment substantially perpendicularly to the surface 4 of the
substrate 2 and is adapted to feed first starting material A
substantially in the direction of the first rotation axis 15 via
the starting material zone 11.
[0022] In case of a moving web as in FIG. 3, sources according to
FIGS. 1, 2A and 2B could of course also be used, one of more of
which could be placed over the web 2 and which could extend from
one edge of the web 2 to another, wherein the whole web 2 would
pass below the source 6. Such sources according to FIGS. 1 and 2
would be moved over a moving web reciprocally, whereupon the number
of deposition layers would increase, when the surface of the web 2
would be exposed alternately to the first starting material A fed
through source 6 and to the second starting material B present in
atmosphere 1.
[0023] In FIG. 4 there is shown a schematical side view of the
source 8 according to an embodiment of the present invention for
feeding first starting material A on the surface 4 of the substrate
2. The source 8 is again positioned in the atmosphere 1, which
comprises second starting material B. The source 8 comprises a gas
feeding member 5 for feeding first starting material A on the
surface 4 of the substrate 2 as well as a second rotation axis 17,
about which the gas delivery means 5 is rotatable. Gas feeding
member 5 is preferably a cylindrical part which has substantially
circular cross section. Alternatively the gas feeding member 5 may
also have a cross section of another shape, such as oval, triangle,
square or some other polygonal shape. The length of the gas feeding
member 5 in the direction of the second rotation axis 17 may vary
according to each application and may be adapted to correspond
substantially for example the width of the substrate, such as
material web, being treated. It is essential, that the present
invention is not limited to any single form of gas feeding member 5
but that the gas feeding member 5 may be realized in any shape.
However the gas feeding member 5 is preferably rotationally
symmetrical relative to the second rotation axis 17. In addition,
the second rotation axis 17 is positioned to pass preferably along
the centre axis of the gas feeding member 5.
[0024] The gas feeding member 5 is adapted to feed a first starting
material A substantially in a transversal direction in relation to
the second rotation axis 17. According to FIG. 4 the gas feeding
member 5 is provided with one or more starting material zone(s) 12,
adapted to feed first starting material A. The gas feeding member 5
may also comprise one or more flushing agent zone(s) (not shown)
for feeding flushing agent. In addition, the gas feeding member 5
may be provided with one or more suction zone(s) 31 for drawing and
discharging first starting material A or flushing agent. According
to FIG. 4, the starting material zones 12 and the suction zones 31
are provided to extend substantially in the direction of the second
rotation axis 17 of the gas feeding member 5. In other words the
starting material zones 12 and the suction zones 31 are
longitudinal channels, which extend along the length of the gas
feeding member 5. Alternatively the starting material zones 12 and
the suction zones 31 may also be shorter and may extend only a part
of the length of the gas feeding member 5, whereupon two or more of
these may be present also in the direction of the second rotation
axis 17 successively in the same line.
[0025] As described previously, first starting material A may be
fed from the gas feeding member 5 via the starting material zone 12
substantially transversally, perpendicularly or radially in
relation to the second rotation axis 17. The gas feeding member 5
may also comprise one or more flushing agent zone(s) (not shown)
for feeding flushing agent on the surface 4 of the substrate 2.
[0026] Suction zones 31 may be provided on the gas feeding member 5
in the same manner as with the aforementioned starting material
zones 12. By means of suction zones 31 first starting materials A
or flushing agents or both may be removed from the surface 4 of the
substrate 2 or proximity thereof. Suction zones 31 are preferably
provided to remove starting materials or flushing agents from the
surface 4 of the substrate or proximity thereof substantially in
transversal direction, perpendicular direction or radially in
relation to the second rotational axis 17 of the gas feeding member
5. By this source 8 according to FIG. 4 the surface 4 of the
substrate 2 may be exposed to a first starting material A and at
the same time by means of the suction zones an excess first
starting material A may be drawn from the surface 4 of the
substrate 2. This source 8 or the gas feeding member 5 thereof may
be moved also in horizontal direction, for example with a
reciprocating movement over the surface 4 of the substrate 2. The
rotational movement of the gas feeding member 5 about the second
rotational axis 17 permits to feed quickly the first starting
material A and thus combined to the horizontal movement to deposit
quickly the substrate 2, when the second starting material B is in
atmosphere 1. When the gas feeding member 5 is positioned at a
distance from the surface of the substrate 2, the second starting
material B is able to flow below the gas feeding member 5 when the
starting material zone 12 is not exactly towards the surface of the
substrate 2. By means of the suction zones 31 absorption of the
second starting material B under the gas feeding member 5 may be
enhanced. Then the surface 4 of the substrate 2 may be exposed both
to the first and the second starting material A, B even though the
gas feeding member 5 is not moved in a horizontal direction
relative to the substrate 2.
[0027] In FIG. 5 there is shown a schematic cross section of the
source 8 of FIG. 4, which comprises a gas feeding member 5, which
is rotatable about a second rotation axis 17. The gas feeding
member 5 comprises several starting material zones 12 for feeding
first starting material A. The starting material zones 12 and the
suction zones 31 are preferably positioned alternately in the
direction of the circumference of the gas feeding member 5, as
shown in the cross sectional view 5. There may be one or more gas
feeding zones 12, and one or more, or none, suction zones 31. The
first starting material A may be fed in all cases alone or it may
be fed by means of a carrier gas. Carrier gas may be fed together
with the first starting material A so that the carrier gas carries
the first starting material A on the surface 4 of the substrate 2
however without participating in the surface reaction itself. The
carrier gas is preferably an inert gas, like nitrogen, which does
not react with the first starting material A.
[0028] According to FIG. 5, the gas feeding member 5 is adapted,
according to arrows shown therein, to feed first starting material
A substantially transversally or radially in relation to the second
rotation axis 17. Preferably the gas feeding member 5 is adapted to
feed first starting material A substantially in a perpendicular
direction in relation to the second rotation axis 17. In the
simplest form of the present invention the gas feeding member 5
comprises only one starting material zone 12, through which first
starting material A may be fed. The source 8 or the gas feeding
member 5 is preferably arranged so that the second rotation axis 17
extends substantially in the direction of the surface 4 of the
substrate 2.
[0029] In the embodiment of FIG. 5 the source 8 comprises a suction
enclosure 30, which provides a suction chamber 35, which has
suction apertures 42. The suction enclosure 30 further comprises a
flow aperture 50, which extends substantially in the direction of
the second rotation axis 17 of the gas feeding member and through
which the first starting material A and any flushing agents are fed
on the surface 4 of the substrate 2 and respectively removed from
the surface 4 of the substrate 2. The flow aperture 50 is made
narrow in the direction perpendicular to the second rotation axis
17 relative to the diameter of the gas feeding member 5 so that the
fed first starting material A or flushing agent does not spread
over a large area. In addition, the suction enclosure 30 is
provided with a first and a second flange 52, 54, which extend from
the edge of the flow aperture 50 in the direction of the surface 4
of the substrate 2 away from the flow aperture 5 according to FIG.
5 and along the length of the second rotation axis 17 of the gas
feeding member 5. Flanges 52, 54 provide a diffusion barrier
preventing the flow of gases from the feed aperture 50 to the
environment and from the environment to the flow aperture 50
however allowing thus the surface 4 of the substrate 2 to be
exposed efficiently to the first starting material A at the
location of the flow aperture 50. It is to be noted, that in
certain embodiments the flange may also be provided to only one
side of the flow aperture 50. Flanges 52, 54 or one of them may be
replaced by other type of diffusion barriers. Such a source
comprising a suction enclosure does not allow the first starting
material A to pass into the atmosphere 1, which has a second
starting material B, whereupon unwanted reactions of starting
materials may be avoided. Such an enclosed source 8 is preferably
movable over the surface 4 of the substrate 2 relative to the
substrate so that the surface 4 of the substrate 2 is exposed upon
sweeping of source 8 to the first starting material A and after the
sweeping to the second starting material B present in the
atmosphere.
[0030] Above, with reference to FIGS. 1 to 5 different sources 6,
7, 8 are described, which are all adapted to expose locally the
surface 4 of the substrate 2 to a first starting material A. The
facts described in connection with each source 6, 7, 8 concerning
the movement of the source or the gas feeding member 3, 5 thereof
relative to the substrate and placing above the substrate are valid
for all sources 6, 7, 8. In addition, the apparatus according to
the invention may comprise one or more sources 6, 7, 8 and they may
be positioned in such a manner that the substrate 2 is exposed to
the second starting material present in the atmosphere 1 between
the sources 6, 7, 8. The source 6, 7, 8 may be positioned inside
into a separate deposition chamber (not shown), which has an
atmosphere 1, which comprises the second starting material B. The
deposition chamber may be provided so that the substrate or the
substrates are brought through the deposition chamber or
alternatively the substrate is placed inside the deposition chamber
and the deposition chamber is closed for the processing time
according to the batch process. Vacuum or overpressure may be
inside the deposition chamber, or it may be at normal atmospheric
pressure (NTP; 1 bar, 0.degree. C.). Alternatively the source 6, 7,
8 is not positioned inside a separate deposition chamber but the
source 6, 7, 8 is positioned directly in the room space, process
space or in connection with another apparatus or chamber in which
the atmosphere 1 comprises a second starting material B. In a
preferred embodiment, the apparatus comprises feeding means (not
shown) for feeding second starting material B into the atmosphere 1
surrounding the source 6, 7, 8, such as a deposition chamber,
process space or other corresponding space. The feeding means may
comprise a starting material container, a possible pump, a tubing
for conducting the second starting material B into the atmosphere 1
surrounding the source 6, 7, 8 or the deposition chamber as well as
a feeding member, like a nozzle or other corresponding terminal
device for feeding the second starting material B into the
atmosphere 1 or the deposition chamber. In a preferred embodiment
the feeding means for feeding second starting material B are
stationary and provided for example in the deposition chamber so
that the second starting material may be fed in the deposition
chamber through the wall thereof. In other words, the feeding means
for feeding the second starting material B and the source 6, 7, 8
are separated in relation to each other and thus the feeding of the
second starting material B is independent of the movement of the
source 6, 7, 8 and the feedings of the first and the second
starting material A, B are independent of each other. Thus the
first starting material A is adapted to be fed via the source 6, 7,
8 locally on the surface of the substrate and the second starting
material B is fed separately into the atmosphere 1 surrounding the
source 6, 7, 8 independently of the source 6, 7, 8 and separately
thereof. This means that the second starting material 1 is not fed
according to the invention from the source 6, 7, 8. The second
starting material B is thus not fed actively on the surface of the
substrate and it, but the second starting material B is located, or
is brought, only passively in the atmosphere surrounding the source
6, 7, 8, whereupon the surface of the substrate is exposed to the
second starting material B continuously when it is not exposed to
the first starting material A under the influence of the source 6,
7, 8.
[0031] The apparatus according to the present invention for
processing a surface 4 of a substrate 2 by exposing the surface 4
of the substrate 2 to alternating surface reactions of at least a
first starting material A and a second starting material B
according to the principles of atomic layer deposition method may
comprise one or more of the aforementioned sources 6, 7, 8. The
source 6, 7, 8 is adapted to feed a first starting material A
locally on the surface 4 of the substrate 2. The source is further
positioned in the atmosphere 1, which comprises second starting
material B. The source 6, 7, 8 is further adapted to be movable in
relation to the substrate 2 on the surface 4 thereof or in the
proximity of the source 4 so that with the source 6, 7, 8 it is
possible to sweep over the surface 4 by exposing locally the
surface 4 at the same time to a first starting material. After the
sweeping the source 6, 7, 8 moves away from the part of the surface
4 swept, whereupon the part of the surface 4 swept is exposed to
the second starting material present in the atmosphere 1. Exposure
to starting materials A and B produces always a surface reaction on
the surface 4 of the substrate 2 according to the principles of the
ALD method, In all of the embodiments of the sources 6, 7, 8
described above the source 6, 7, 8 is adapted to be movable on the
surface 4 of the substrate 2 or in the proximity thereof in
relation to the substrate (2) for performing the sweeping. This
means that the source 6, 7, 8 may be moved on the surface of the
substrate, the substrate 2 may be moved in relation to a stationary
source 6, 7, 8 or both the source 6, 7, 8 and the substrate 2 may
be moved. The movement of the source 6, 7, 8 may be a transferring
movement occurring on a plane, a reciprocating movement or a
rotating movement or a combination thereof. The apparatus according
to the invention may comprise two or more sources 6, 7, 8, which
are separated from each other by a slit or a space in flow
connection with the surrounding atmosphere 1 in order to expose the
surface 4 of the substrate 2 to a second starting material B in
between the sources. Alternatively each source 6, 7, 8 may comprise
or more starting material zones 10, which are separated from each
other with a slit or a space in flow connection with the
surrounding atmosphere 1 in order to expose the surface 4 of the
substrate 2 to a second starting material B in between the starting
material zones 10. It is also possible to provide a source 6, 7, 8,
which comprises two or more starting material members 3, 5, which
are separated from each other by a slit or a space opening to the
surrounding atmosphere 1 in order to expose the surface 4 of the
substrate 2 to a second starting material B in between the starting
material feeding members 3, 5.
[0032] As starting materials A and B any starting materials
typically used in the ALD method may be used. As a first starting
material A for example TMA (trimethyl aluminium) may be used, and
as the second starting material B water steam. In certain
applications the second starting material B may be reactive or non
reactive, air or oxygen. Alternatively the first and the second
starting material A, B may also be plasma or radical or may be
arranged to provide a sparkle.
[0033] The present invention further relates to a method for
processing the surface 4 of the substrate 2 by exposing the surface
4 of the substrate 2 to alternating surface reactions of at least a
first starting material A and a second starting material B
according to the principles of atomic layer deposition method. The
method includes feeding on the surface 4 of the substrate 2 locally
a first starting material A by using the source 6, 7, 8 by moving
the source 6, 7, 8 in relation to the substrate 2, and exposing the
surface 4 of the substrate 2 processed with the first starting
material A to a second starting material B present in an atmosphere
1 surrounding the source 6, 7, 8. In other words, according to the
present invention the second starting material B may be fed into
the atmosphere 1 surrounding the source 6, 7, 8, such as a
deposition chamber, and thus to expose the surface of the substrate
to the second starting material B. The second surface material B is
fed into the atmosphere 1 preferably independently of the source 6,
7, 8. In other words, the second starting material is fed
preferably from one or more stationary feeding point(s) into the
atmosphere 1. Then the concentration of the second starting
material B may be obtained stable in the atmosphere 1 surrounding
the source 6, 7, 8 independently of the movement of the source 6,
7, 8. This further ensures a stable deposition result. As described
before, the feeding of the first feeding material A and the second
feeding material B are independent of each other and the movement
of the source 6, 7, 8. Further, it is to be noted that in every
case the feeding of the second material B is not necessary, if for
example humidity present in the air is sufficient as a second
starting material B. The surface of the substrate is thus exposed
actively by means of the source 6, 7, 8 to the first starting
material A and passively to the second starting material B present
in the atmosphere. The moving of the source 6, 7, 8 is performed in
the method as described hereinbefore. Thus the surface 4 of the
substrate 2 is exposed alternately to the first starting material A
fed by the source 6, 7, 8 and to the second starting material B
present in the atmosphere 1.
[0034] Although several embodiments and features according to the
present invention are described hereinbefore, all of which are not
shown in the accompanied embodiment, it is clear that all of the
features shown may be combined in order to provide in each case the
preferred embodiment.
[0035] It is clear to a person in the art that with technical
developments the basic idea may be realized in many different ways.
Thus the invention and the embodiments thereof are not limited to
the examples shown hereinbefore but may instead vary within the
frames of the claims.
* * * * *