U.S. patent application number 16/360187 was filed with the patent office on 2019-07-18 for process kit components for use with an extended and independent rf powered cathode substrate for extreme edge tunability.
The applicant listed for this patent is APPLIED MATERIALS, INC.. Invention is credited to SAMER BANNA, GARY LERAY, VALENTIN TODOROW, ALBERT WANG, IMAD YOUSIF.
Application Number | 20190221463 16/360187 |
Document ID | / |
Family ID | 48609328 |
Filed Date | 2019-07-18 |
United States Patent
Application |
20190221463 |
Kind Code |
A1 |
TODOROW; VALENTIN ; et
al. |
July 18, 2019 |
PROCESS KIT COMPONENTS FOR USE WITH AN EXTENDED AND INDEPENDENT RF
POWERED CATHODE SUBSTRATE FOR EXTREME EDGE TUNABILITY
Abstract
Process kit components for use with a substrate support of a
process chamber are provided herein. In some embodiments, a process
kit ring may include a ring shaped body having an outer edge, an
inner edge, a top surface and a bottom, wherein the outer edge has
a diameter of about 12.473 inches to about 12.479 inches and the
inner edge has a diameter of about 11.726 inches to about 11.728
inches, and wherein the ring shaped body has a height of about
0.116 to about 0.118 inches; and a plurality of protrusions
disposed on the top surface of the ring shaped body, each of the
plurality of protrusions disposed symmetrically about the ring
shaped body.
Inventors: |
TODOROW; VALENTIN; (PALO
ALTO, CA) ; BANNA; SAMER; (SAN JOSE, CA) ;
YOUSIF; IMAD; (SAN JOSE, CA) ; WANG; ALBERT;
(CONCORD, CA) ; LERAY; GARY; (MOUNTAIN VIEW,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
APPLIED MATERIALS, INC. |
Santa Clara |
CA |
US |
|
|
Family ID: |
48609328 |
Appl. No.: |
16/360187 |
Filed: |
March 21, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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13651354 |
Oct 12, 2012 |
|
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16360187 |
|
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61576324 |
Dec 15, 2011 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01J 37/32642 20130101;
H01L 21/6833 20130101; H01L 21/6831 20130101; Y10T 279/23 20150115;
H01J 37/32715 20130101; H02N 13/00 20130101 |
International
Class: |
H01L 21/683 20060101
H01L021/683; H01J 37/32 20060101 H01J037/32; H02N 13/00 20060101
H02N013/00 |
Claims
1. A process kit ring for use with a substrate support of a process
chamber, comprising: a ring-shaped body having an outer edge, an
inner edge, a top surface and a bottom, wherein the outer edge has
a diameter of about 15.115 inches to about 15.125 inches and
wherein the inner edge has a diameter of about 11.752 inches to
about 11.757 inches, and wherein the ring-shaped body has a
thickness of about 0.510 inches to about 0.520 inches; a first step
and a second step formed in the ring-shaped body between the outer
edge and inner edge, wherein the first step has an outer diameter
of about 12.077 inches to about 12.087 inches, and wherein the
second step has an outer diameter of about 11.884 inches to about
11.889 inches; and a ring extending downward from the bottom of the
ring shaped body proximate the outer edge of the ring shaped body,
the ring having an inner diameter of about 14.905 inches to about
14.915 inches.
2. The process kit ring of claim 1, wherein a transition from a top
surface of the second step to the top surface of the ring-shaped
body has an angle of about 99 degrees to about 101 degrees with
respect to the top surface of the ring shaped body.
3. The process kit ring of claim 1, wherein the inner edge
comprises a flat portion configured to interface with a portion of
the substrate support.
4. A process kit ring for use with a substrate support of a process
chamber, comprising: a ring-shaped body having an outer edge, an
inner edge, a top surface and a bottom, wherein the outer edge has
a diameter of about 15.115 inches to about 15.125 inches and
wherein the inner edge has a diameter of about 12.245 inches to
about 12.250 inches, and wherein the ring shaped body has a
thickness of about 0.520 inches to about 0.530 inches; and a
plurality of protrusions disposed symmetrically about the inner
edge of the ring shaped body, the plurality of protrusions
extending inwardly from the inner edge towards a center of the ring
shaped body.
5. The process kit ring of claim 4, wherein the process kit ring is
fabricated from quartz (SiO.sub.2).
6. The process kit ring of claim 4, wherein the plurality of
protrusions comprise three protrusions disposed about 120 degrees
from one another about the inner edge of the ring shaped body.
7. The process kit ring of claim 4, wherein a distance from a
center of the ring shaped body to a terminal end of each of the
plurality of protrusions is about 5.937 inches to about 5.947.
8. The process kit ring of claim 4, wherein each of the plurality
of protrusions has a terminal end that is rounded.
9. The process kit ring of claim 4, wherein a substrate supporting
surface of each of the plurality of protrusions is disposed beneath
the top surface of the ring shaped body.
10. The process kit ring of claim 4, further comprising a notch
formed in the ring shaped body beneath the inner edge of the ring
shaped body, the notch having an outer diameter of about 12.405
inches to about 12.505 inches.
11. The process kit ring of claim 4, further comprising a curved
transition between a substrate supporting surface of each of the
plurality of protrusions and the top surface of the ring shaped
body.
12. The process kit ring of claim 4, further comprising a tapered
portion extending from the inner edge of the ring shaped body to
the top surface of the ring shaped body, wherein an angle between
the tapered portion and the top surface of the ring shaped body is
about 99 degrees to about 101 degrees.
13. The process kit ring of claim 4, further comprising: a ring
extending downward from the bottom of the ring shaped body
proximate an outer edge of the body, the ring having an inner
diameter of about 14.905 inches to about 14.915 inches.
14. A set of process kit rings for use with a substrate support of
a process chamber, comprising: a first ring having a ring-shaped
body having an outer edge, an inner edge, a top surface and a
bottom, wherein the outer edge has a diameter of about 12.473
inches to about 12.479 inches and the inner edge has a diameter of
about 11.726 inches to about 11.728 inches, and wherein the
ring-shaped body has a thickness of about 0.116 to about 0.118
inches; and a second ring disposed on an upper surface of the first
ring and configured to extend a height of the set of process kit
rings above a processing surface of the substrate.
15. The set of process kit rings of claim 14, wherein the second
ring is a singular piece.
16. The set of process kit rings of claim 14, wherein the second
ring comprises multiple pieces stacked or interconnected
together.
17. The set of process kit rings of claim 14, further comprising: a
third ring disposed below the first and second rings and configured
to isolate a grounding layer disposed below the second ring and
prevent arching between the grounding layer and other chamber
components.
18. The set of process kit rings of claim 14, wherein the first and
second rings are fabricated from silicon carbide (SiC).
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. patent application
Ser. No. 13/651,354, filed Oct. 12, 2012 which claims benefit to
co-pending U.S. provisional patent application Ser. No. 61/576,324,
filed Dec. 15, 2011 and U.S. provisional patent application Ser.
No. 61/691,077, filed Aug. 20, 2012, each of which are herein
incorporated by reference in their entireties
FIELD
[0002] Embodiments of the present invention generally relate to
substrate processing equipment.
BACKGROUND
[0003] Substrate processing systems, such as plasma reactors, may
be used to deposit, etch, or form layers on a substrate or
otherwise treat surfaces of the substrate. One technique useful for
controlling aspects of such substrate processing is use of radio
frequency (RF) energy to control a plasma proximate the substrate,
such as by coupling RF energy to an electrode disposed beneath a
substrate disposed on a substrate support.
[0004] The inventors provide herein embodiments of substrate
processing systems that may provide improved RF energy control of
the substrate processing system, and flexible control of plasma
sheath at the vicinity of the wafer edge.
SUMMARY
[0005] Process kit components for use with a substrate support of a
process chamber is provided herein. In some embodiments, a process
kit ring may include a ring shaped body having an outer edge, an
inner edge, a top surface and a bottom, wherein the outer edge has
a diameter of about 12.473 inches to about 12.479 inches and the
inner edge has a diameter of about 11.726 inches to about 11.728
inches, and wherein the ring shaped body has a height of about
0.116 to about 0.118 inches; and a plurality of protrusions
disposed on the top surface of the ring shaped body, each of the
plurality of protrusions disposed symmetrically about the ring
shaped body.
[0006] In some embodiments, a process kit ring for use with a
substrate support of a process chamber may include a ring shaped
body having an outer edge, an inner edge, a top surface and a
bottom, wherein the outer edge has a diameter of about 15.115
inches to about 15.125 inches and wherein the inner edge has a
diameter of about 11.752 inches to about 11.757 inches, and wherein
the ring shaped body has a thickness of about 0.510 inches to about
0.520 inches; a first step and a second step formed in the ring
shaped body between the outer edge and inner edge, wherein the
first step has an outer diameter of about 12.077 inches to about
12.087 inches, and wherein the second step has an outer diameter of
about 11.884 inches to about 11.889 inches; and a ring extending
downward from the bottom of the ring shaped body proximate the
outer edge of the ring shaped body, the ring having an inner
diameter of about 14.905 inches to about 14.915 inches.
[0007] In some embodiments, a process kit ring for use with a
substrate support of a process chamber may include a ring shaped
body having an outer edge, an inner edge, a top surface and a
bottom, wherein the outer edge has a diameter of about 15.115
inches to about 15.125 inches and wherein the inner edge has a
diameter of about 12.245 inches to about 12.250 inches, and wherein
the ring shaped body has a thickness of about 0.520 inches to about
0.530 inches; a plurality of protrusions disposed symmetrically
about the inner edge of the ring shaped body, the plurality of
protrusions extending inwardly from the inner edge towards a center
of the ring shaped body; and a ring extending downward from the
bottom of the ring shaped body proximate an outer edge of the body,
the ring having an inner diameter of about 14.905 inches to about
14.915 inches.
[0008] Other and further embodiments of the present invention are
described below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Embodiments of the present invention, briefly summarized
above and discussed in greater detail below, can be understood by
reference to the illustrative embodiments of the invention depicted
in the appended drawings. It is to be noted, however, that the
appended drawings illustrate only typical embodiments of this
invention and are therefore not to be considered limiting of its
scope, for the invention may admit to other equally effective
embodiments.
[0010] FIG. 1 depicts schematic view of a plasma reactor in
accordance with some embodiments of the present invention.
[0011] FIG. 2 depicts a schematic view of a substrate support in
accordance with some embodiments of the present invention.
[0012] FIG. 3 depicts a partial schematic view of a substrate
support in accordance with some embodiments of the present
invention.
[0013] FIG. 4 depicts a partial schematic view of a substrate
support in accordance with some embodiments of the present
invention.
[0014] FIGS. 5A-B respectively depict a top view and a side
cross-sectional view of a process kit ring for use in a plasma
reactor in accordance with some embodiments of the present
invention.
[0015] FIGS. 6A-C respectively depict a top view, a side
cross-sectional view, and a detail of the side cross-sectional view
of a process kit ring for use in a plasma reactor in accordance
with some embodiments of the present invention.
[0016] FIGS. 7A-E respectively depict a top view, a side
cross-sectional view, a detail of the side cross-sectional view, a
detail of the top view, and a side cross sectional view of the top
detail of a process kit ring for use in a a plasma reactor in
accordance with some embodiments of the present invention.
[0017] To facilitate understanding, identical reference numerals
have been used, where possible, to designate identical elements
that are common to the figures. The figures are not drawn to scale
and may be simplified for clarity. It is contemplated that elements
and features of one embodiment may be beneficially incorporated in
other embodiments without further recitation.
DETAILED DESCRIPTION
[0018] Methods and apparatus for processing substrates are
disclosed herein. The inventive methods and apparatus may
advantageously may facilitate more uniform plasma processing of
substrates as compared to conventional plasma processing apparatus.
For example, embodiments of the invention may reduce edge roll off
or edge roll up at the edge of the substrate, thereby providing a
more uniform substrate. The inventors have observed that edge roll
off or roll up may be caused by, amongst other factors,
discontinuity in RF power coupling proximate the edge of the
substrate. The inventive methods and apparatus addresses
discontinuity at the edge of the substrate by providing an
electrode, or providing one or more additional electrodes, to
improve RF power coupling proximate the edge of the substrate.
[0019] FIG. 1 depicts a schematic side view of an inductively
coupled plasma reactor (reactor 100) in accordance with some
embodiments of the present invention. The reactor 100 may be
utilized alone or, as a processing module of an integrated
semiconductor substrate processing system, or cluster tool, such as
a CENTURA.RTM. integrated semiconductor wafer processing system,
available from Applied Materials, Inc. of Santa Clara, Calif.
Examples of suitable plasma reactors that may advantageously
benefit from modification in accordance with embodiments of the
present invention include inductively coupled plasma etch reactors
such as the DPS.RTM. line of semiconductor equipment or other
inductively coupled plasma reactors, such as MESA.TM. or the like
also available from Applied Materials, Inc. The above listing of
semiconductor equipment is illustrative only, and other etch
reactors, and non-etch equipment (such as CVD reactors, or other
semiconductor processing equipment) may also be suitably modified
in accordance with the present teachings. For example, suitable
exemplary plasma reactors that may be utilized with the inventive
methods disclosed herein may be found in U.S. patent application
Ser. No. 12/821,609, filed Jun. 23, 2010 by V. Todorow, et al., and
entitled, "INDUCTIVELY COUPLED PLASMA APPARATUS," or U.S. patent
application Ser. No. 12/821,636, filed Jun. 23, 2010 by S. Banna,
et al., and entitled, "DUAL MODE INDUCTIVELY COUPLED PLASMA REACTOR
WITH ADJUSTABLE PHASE COIL ASSEMBLY."
[0020] The reactor 100 generally includes a process chamber 104
having a conductive body (wall) 130 and a lid 120 (e.g., a ceiling)
that together define an inner volume, a substrate support 116
disposed within the inner volume (shown supporting a substrate
115), an inductively coupled plasma apparatus 102, and a controller
140. The wall 130 is typically coupled to an electrical ground 134.
In embodiments where the reactor 100 is configured as an
inductively coupled plasma reactor; the lid 120 may comprise a
dielectric material facing the inner volume of the reactor 100.
[0021] The substrate support 116 generally includes a support
surface for supporting the substrate 115. The support surface may
be formed from a dielectric material. In some embodiments, the
substrate support 116 may include a cathode coupled through a
matching network 124 to a bias power source 122. The bias source
122 may illustratively be a source of up to about 1000 W (but not
limited to about 1000 W) of RF energy at a frequency of, for
example, approximately 13.56 MHz, although other frequencies and
powers may be provided as desired for particular applications. The
bias source 122 may be capable of producing either or both of
continuous or pulsed power. In some embodiments, the bias source
122 may be a DC or pulsed DC source. In some embodiments, the bias
source 122 may be capable of providing multiple frequencies, or one
or more second bias sources (as illustrated in FIG. 2) may be
coupled to the substrate support 116 through the same matching
network 124 or through one or more additional matching networks (as
illustrated in FIG. 2) to provide multiple frequencies.
[0022] FIG. 2 depicts further detail of the substrate support 116
in accordance with some embodiments of the present invention. As
shown in FIG. 2, the substrate support 116 may include a first
electrode 200 disposed within the substrate support 116. In some
embodiments, the first electrode 200 may be centrally disposed
beneath the support surface 216 of the substrate support 116. The
first electrode 200 may be formed of a conductive material, such as
one or more of aluminum (AI), doped silicon carbide (SiC), or other
suitable conductive materials that are compatible with process
environment. In some embodiments, the first electrode 200 may be
disposed in, or may be, a body 205 that supports the dielectric
support surface of the substrate support 116. The body 205 may have
a peripheral edge 202 and a first surface 204. In some embodiments,
the body 205 may include a plurality of channels 207 disposed
through the body 205 to flow a heat transfer medium through the
channels 207. A heat transfer medium source 209 may be coupled to
the plurality of channels 207 to provide a heat transfer medium to
the plurality of channels 207. For example, the flow of the heat
transfer medium through the plurality of channels 207 may be used
to regulate the temperature of a substrate disposed on the
substrate support 116.
[0023] A second electrode 206 may be disposed within the substrate
support 116. The second electrode 206 may have a second surface 208
disposed about and above the first surface 204 of the first
electrode 200. The second electrode 206 may extend radially from
the first electrode 204, for example, such as beyond the peripheral
edge 202 of the first electrode 200 as discussed below. The second
electrode 206 may be formed of any suitable conductive materials,
such as one or more of AI, doped SiC, doped diamond, or other
suitable conductive materials that are compatible with process
environment. In some embodiments, the second electrode 206 may be
electrically coupled to the first electrode 200, such that the
first and second electrodes 200, 206 may be coupled to a common RF
power supply (e.g., bias source 122). In some embodiments, the
first and second electrodes 200, 206 may be a single integrated
electrode formed to a shape suitable to provide the functions
taught herein. Alternatively, in some embodiments, the second
electrode 206 may be electrically isolated from the first electrode
200, such that the first and second electrodes 200, 206 may be
individually controlled by the same or separate RF power
supplies
[0024] For example, in some embodiments, the bias power source 122
(e.g., a first RF power supply) may be coupled to each of the first
and second electrodes 200, 206 to provide RF energy to the first
and second electrodes 200, 206. In such embodiments, the first and
second electrodes 200, 206 may be electrically coupled (either as a
single integrated electrode, or as separate electrodes) or may be
electrically isolated. Alternatively, the bias power source 122 may
be coupled to the first electrode 200 to provide RF energy to the
first electrode 200 and a second power supply 210 (shown in
phantom) may be coupled to the second electrode 206 via a matching
network 211 (shown in phantom) to provide RF energy to the second
electrode 206. For example, to electrically isolate the first and
second electrodes 200, 206, a dielectric layer 213 (shown in
phantom) may be disposed between the first and second electrodes
200, 206 as illustrated in FIG. 2. Alternatively, some embodiments
of a base 212 (discussed below) may be used to electrically isolate
the first and second electrodes 200,206.
[0025] In some embodiments, a base 212 may be disposed on the first
electrode 200. In embodiments where the first and second electrodes
200, 206 are electrically coupled, the base 212 may be a conductive
ring or the like disposed about at least a portion of the first
electrode 200, as illustrated in FIG. 2. Alternatively, the base
212 may have conductive pathways disposed about the first electrode
200
[0026] The base 212 may be fabricated, in whole or in part, from a
dielectric material suitable to prevent arcing between the first
and second electrodes 200, 206. The second electrode 206 includes a
radially extending portion 214 disposed atop the base 212 that
extends beyond the peripheral edge 202 of the first electrode 200.
The base 212 and the radially extending portion 214 may be a single
integrated component or separate components that may be assembled
together to form the second electrode 206. The position of the
second surface 208 of the second electrode 206 may be positioned to
control the RF energy coupling proximate the periphery of a
substrate disposed on the substrate support 116 during processing.
In addition, the length to which the radially extending portion 214
extends beyond the peripheral edge 202 of the first electrode 200
may be adjusted to achieve the desired RF energy coupling proximate
the periphery of the substrate disposed on the substrate support
116. In some embodiments, the height of the base 212 and/or the
thickness of the radially extending portion 214 may together define
the position of the second surface 208 with respect to the first
surface 204.
[0027] The substrate support may include a substrate support
surface 216 disposed above the first surface 204 of the first
electrode 200. For example, the substrate support surface 216 may
be part of an electrostatic chuck 218. The electrostatic chuck 218
may be disposed above the first electrode 200 and the substrate
support surface 216 may be an upper surface of the electrostatic
chuck 218. The electrostatic chuck 218 may include a dielectric
plate, such as a ceramic puck 220, as illustrated in FIG. 2. The
ceramic puck 220 may include an electrode 222 disposed therein to
provide DC energy for chucking a substrate 115 to the electrostatic
chuck 218. The electrode 222 may be coupled to a DC power supply
226.
[0028] An edge ring 228 may be disposed about the electrostatic
chuck 218. For example, the edge ring 228 may be a process kit, or
the like, designed to improve processing proximate the peripheral
edge of the substrate 224 and/or to protect the substrate support
from undesired plasma exposure during processing. The edge ring 228
may be dielectric or may have an outer dielectric layer, for
example, such as comprising one or more of quartz, yittria
(Y.sub.2O.sub.3), aluminum nitride (AlN), diamond coated silicon
carbide (SiC) or the like. In some embodiments, such as illustrated
in FIG. 2, the edge ring 228 may about equal in height with a
processing surface of the substrate 115 when disposed on the
electrostatic chuck 218. Alternatively, the height of the edge ring
relative to the processing surface of the substrate resting on the
electrostatic chuck 218 may vary. For example, in some embodiments,
such as illustrated in FIG. 3, an edge ring 300 may have a height
that is higher that the processing surface of the substrate 115.
The edge ring may be a singular piece constructed of one material,
such as the edge ring 300. Alternatively, additional rings may be
used to extend the height of the edge ring above the processing
surface of the substrate 115, such as a ring 302 which may rest on
and/or be fitted/stacked on the edge ring 300. For example, the
edge ring 300 and the ring 302 may comprise the same materials.
Alternatively, the edge ring 300 and the ring 302 may comprise
different materials, for example, such as the edge ring 300 may
comprise quartz and the ring 302 may comprise SiC. The height of
the edge ring (e.g., edge ring 300 or a combination of edge ring
300 and ring 302) above the processing surface of the substrate 115
may be optimized to improve uniformity of the plasma proximate the
peripheral edge of the substrate 115.
[0029] Returning to FIG. 2, the edge ring 228 may be disposed above
and adjacent to the radially extending portion 214 of the second
electrode 206 such that the edge ring 228 may be disposed between
the extending portion 214 and a grounding layer 230. For example,
the edge ring 228 may be formed of a singular piece such that the
edge ring 228 separates the extending portion 214 from the
grounding layer 230. Alternatively, as illustrated in FIG. 2, a
ring 232, such as a dielectric spacer or the like may be disposed
below the edge ring 228 and between the extending portion 214 of
the second electrode 206 and the grounding layer 230. In either
embodiment, i.e., with or without the ring 232, it may be desired
to have the extending portion 214 sufficiently isolated from the
grounding layer 230 such that arcing between the extending portion
214 and the grounding layer 230 is limited and/or prevented.
[0030] The ring 232 may be a singular piece or comprise multiple
pieces stacked or interconnected together as illustrated by the
dotted line in FIG. 2. In embodiments where multiple stacked pieces
are used, the piece may comprise the same or different materials.
In some embodiments, other rings may be utilized or one or more
pieces may be removed to accommodate a larger extending portion of
the second electrode 206. As illustrated in FIG. 4, a ring 400 may
be utilized to accommodate a larger extending portion 402 (e.g.,
larger than the extending portion 214). As illustrated, the
extending portion 402 may extend beyond a first dielectric layer
234 (discussed below). Similar to the ring 232, the ring 400 may be
utilized to sufficiently isolate the extending portion 402 from the
grounding layer 230. The extending portion (e.g., 214 or 402) may
range in length, for example, to optimize uniformity in the plasma
proximate the peripheral edge of the substrate 115. In some
embodiments, the length of the extending portion and the height of
the edge ring may both be optimized to achieve the desired
uniformity in the plasma proximate the peripheral edge of the
substrate 115.
[0031] FIGS. 5A-B respectively depict a top view and a side
cross-sectional view of a ring 502 that may be used as the ring 232
or the ring 400 in accordance with some embodiments of the present
invention. The dimensions of the ring 502 described below
advantageously allow the ring 502 to be suitable for use with the
substrate support 116 described above. In some embodiments, the
ring 502 is fabricated from silicon carbide (SiC). By fabricating
the ring 502 from silicon carbide the ring 502 may advantageously
be resistant to degradation when exposed to a process environment
within the process chamber.
[0032] In some embodiments, the ring 502 may generally comprise a
ring shaped body 504 having an outer edge 511, inner edge 513, a
top surface 515, and a bottom surface 517. In some embodiments, the
body 504 may comprise a plurality of protrusions 506 (three
protrusions 506 shown) extending upwardly from the top surface
515.
[0033] In some embodiments, a diameter of the outer edge 511 may be
about 12.473 inches to about 12.479 inches. In some embodiments, a
diameter of the inner edge 513 may be about 11.726 inches to about
11.728 inches. In some embodiments, the inner edge 513 of the ring
502 comprises a flat portion 509 proximate one of the plurality of
protrusions 506. The flat portion 509 interfaces with a portion of
the substrate support to facilitate proper orientation of the ring
502 when installed on the substrate support. In some embodiments, a
distance 512 from the flat portion 509 to a center 510 of the ring
502 may be about 5.826 inches to about 5.831 inches. In some
embodiments, the flat portion 509 may have a length 508 of about
1.310 inches to about 1.320 inches.
[0034] When present, the plurality of protrusions 506 (three
protrusions 506 shown) support a component of a substrate support
(e.g., the edge ring 228 of substrate support 116 described above)
atop the ring 502 and provide a gap therebetween. In embodiments
where three protrusions 506 are present, the protrusions 506 may be
disposed symmetrically about the body 504. For example, each of the
three protrusions 506 may be separated by an angle 519 of about 120
degrees from one another about the body 504. In addition, each
protrusion 506 may be disposed about the body 504 such a distance
525 between an outer edge 527 of the protrusion 506 and the center
510 of the body 504 is about 6.995 inches to about 6.105 inches. In
some embodiments a distance 523 from an inner edge 529 of the
protrusion 506 to the center 510 of the body 504 is about 5.937
inches to about 5.947 inches.
[0035] Referring to FIG. 5B, in some embodiments, the body 504 may
have a height H1 of about 0.116 inches to about 0.118 inches. The
protrusion 506 may extend from the surface 515 of the body 504 to a
height H2 of about 0.049 inches to about 0.059 inches. In some
embodiments, the protrusion 506 may have a sloped side 531 that is
angled about 9 degrees to about 11 degrees from an axis 533
perpendicular to the surface 515 of the body 504.
[0036] FIGS. 6A-C respectively depict a top view, a side
cross-sectional view, and a detail of the side cross-sectional view
of a process kit ring 602 that may be used as the edge ring 228 or
the edge ring 300 for use in a plasma reactor in accordance with
some embodiments of the present invention. The dimensions of the
process kit ring 602 described below advantageously allow the
process kit ring 602 to be suitable for use with the substrate
support 116 described above. In some embodiments, the process kit
ring 602 is fabricated from quartz (SiO.sub.2). By fabricating the
process kit ring 602 from quartz, the process kit ring 602 may
advantageously be dielectric and resistant to degradation when
exposed to a process environment within the process chamber.
[0037] The process kit ring 602 generally comprises a ring shaped
body 601 having an outer edge 615, inner edge 616, a top surface
604 and a bottom 613. A first step 607 and second step 608 may be
formed between the outer edge 615 and the inner edge 616.
[0038] In some embodiments, a diameter of the outer edge 615 may be
about 15.115 inches to about 15.125 inches. In some embodiments, a
diameter of the inner edge 616 may be about 11.752 inches to about
11.757 inches. In some embodiments, the inner edge 616 of the body
601 comprises a flat portion 617 configured to interface with a
portion of the substrate support to facilitate proper orientation
of the process kit ring 602 when installed on the substrate
support. In some embodiments, a distance 605 between the flat
portion 617 and a center axis of the process kit ring 602 may be
about 5.825 to about 5.830 inches.
[0039] Referring to FIG. 6B, the first step 607 provides an open
area 634 above and about the periphery of a substrate when disposed
on the process kit ring 602 for processing. The open area 634 may
allow for processing and/or may reduce an amount of heat transfer
from the substrate to the process kit ring 602. In some
embodiments, the first step 607 may have an outer diameter 614 of
about 12.077 inches to about 12.087 inches and extend to the outer
diameter 612 of the second step 608. In some embodiments, a
transition 611 from a surface 609 of the second step 608 to the top
surface 604 of the process kit ring 602 may have an angle 629 of
about 99 degrees to about 101 degrees, such as shown in FIG. 6C.
Referring back to FIG. 6B, in such embodiments, an inner diameter
610 of the top surface 604 may be about 12.132 inches to about
12.142 inches.
[0040] The second step 608 provides a supporting surface for a
substrate when disposed on the process kit ring 602 for processing.
The second step 608 may have an outer diameter 612 of about 11.884
inches to about 11.889 inches and extend to the inner edge 616 of
the process kit ring 602.
[0041] In some embodiments, the process kit ring 602 may comprise a
ring 632 extending downward from the bottom 613 of the process kit
ring 602 and about an outer edge 630 of the process kit ring 602.
The ring 632 allows the process kit ring 602 to securely sit atop
the substrate support and allow other components of the substrate
support to fit underneath the process kit ring 602 (e.g., the ring
502 described above). In some embodiments, the ring 632 may have an
inner diameter 633 of about 14.905 inches to about 14.915 inches.
Referring to FIG. 6C, in some embodiments, an overall thickness 620
of the process kit ring 602 may be about 0.510 inches to about
0.520 inches.
[0042] FIGS. 7A-E respectively depict a top view, a side
cross-sectional view, a detail of the side cross-sectional view, a
detail of the top view, and a side cross sectional view of the top
detail of a process kit ring for use in a a plasma reactor in
accordance with some embodiments of the present invention. The
dimensions of the process kit ring 702 described below
advantageously allow the process kit ring 702 to be suitable for
use with the substrate support 116 described above. In some
embodiments, the process kit ring 702 is fabricated from quartz
(SiO.sub.2). By fabricating the process kit ring 702 from quartz,
the process kit ring 702 may advantageously be dielectric and
resistant to degradation when exposed to a process environment
within the process chamber.
[0043] The process kit ring 702 generally comprises a ring shaped
body 704 having an outer edge 705, inner edge 706, a top surface
707 and a bottom 709 and a plurality of protrusions (three
protrusions 716 shown) extending inwardly from the inner edge 706
towards a center 711 of the process kit ring 702.
[0044] In some embodiments, a diameter 708 of the outer edge 705
may be about 15.115 inches to about 15.125 inches. In some
embodiments, a diameter of the inner edge 706 may be about 12.245
inches to about 12.250 inches.
[0045] The plurality of protrusions 716 provides a supporting
surface for a substrate when disposed on the process kit ring 702
for processing. In some embodiments, the plurality of protrusions
716 may be disposed symmetrically about the inner edge 706 of the
process kit ring 702, for example such as disposed about 120
degrees from one another. In some embodiments, each of the
plurality of protrusions 716 extend towards the center 711 of the
process kit ring 702 such that a distance 710 from the center 711
to an end 719 of each of the plurality of protrusions 716 may be
about 5.937 inches to about 5.947 inches.
[0046] Referring to FIG. 7D, in some embodiments, each of the
plurality of protrusions 716 may have a width 731 of about 0.205
inches to about 0.216 inches. In some embodiments, each of the
plurality of protrusions 716 may comprise a rounded end 741.
[0047] Referring to 7E, in some embodiments, a substrate supporting
surface 737 of each of the plurality of protrusions 716 may be
disposed beneath the top surface 707 of the process kit ring 702.
In some embodiments, a transition 735 between the substrate
supporting surface 737 and the top surface 707 of the process kit
ring 702 may be curved.
[0048] Referring to FIG. 7B, in some embodiments, a notch 726 may
be formed beneath the inner edge 706. When present, the notch 726
may interface with another component of the substrate support to
facilitate centering the process kit ring 702 on the component. In
some embodiments, the notch 726 may be formed in the process kit
ring 702 to a diameter 720 of about 12.405 inches to about 12.505
inches. In some embodiments, the process kit ring 702 may comprise
a ring 724 extending downward from the bottom 709 of the process
kit ring 702 about an outer edge 726 of the process kit ring 702.
The ring 724 allows the process kit ring 702 to securely sit atop
the substrate support and allow other components of the substrate
support to fit underneath the process kit ring 702 (e.g., the ring
502 described above). In some embodiments, an inner diameter 722 of
the ring 724 may be about 14.905 inches to about 14.915 inches. In
some embodiments, the inner edge 706 may comprise a tapered portion
739 extending from the inner edge 706 to the top surface 707
thereby providing an inner diameter 718 of about 12.295 inches to
about 12.305 inches proximate the top surface 707 of the process
kit ring 702.
[0049] Referring to FIG. 7C, in such embodiments, an angle 743
between the tapered portion 735 and the surface may be about 99
degrees to about 101 degrees. In some embodiments, an overall
thickness 729 of the process kit ring 702 may be about 0.520 inches
to about 0.530 inches.
[0050] Returning to FIG. 2, the ring 232 (or ring 400) may rest on
a first dielectric layer 234. The first dielectric layer 234 may be
disposed about the peripheral edge 202 of the first electrode 200.
For example, the first dielectric layer 234 may electrically
isolate the first electrode 200 and/or at least a portion of the
second electrode 206 from the grounding layer 230. As illustrated,
the grounding layer 230 may be disposed about the first dielectric
layer 234. In some embodiments, the radially extending portion 214
of the second electrode 206 may be at least partially disposed
above the first dielectric layer 234, as illustrated in FIG. 2. The
first dielectric layer 234 may comprise any suitable dielectric
materials, such as one or more of quartz, yittria (Y.sub.2O.sub.3),
silicon carbide (SiC), diamond coated quartz, or the like. The
grounding layer 230 may comprise any suitable conductive material,
such as one or more of aluminum, doped SiC, doped diamond, or other
suitable conductive materials that are compatible with process
environment. As illustrated in FIGS. 1 and 2, the ground layer 230
may be coupled to a plasma shield 236 which may be disposed about
the substrate support 116, for example, about the first dielectric
layer 234.
[0051] Returning to FIG. 1, in some embodiments, the lid 120 may be
substantially flat. Other modifications of the chamber 104 may have
other types of lids such as, for example, a dome-shaped lid or
other shapes. The inductively coupled plasma apparatus 102 is
typically disposed above the lid 120 and is configured to
inductively couple RF power into the process chamber 104. The
inductively coupled plasma apparatus 102 includes the first and
second coils 110, 112, disposed above the lid 120. The relative
position, ratio of diameters of each coil, and/or the number of
turns in each coil can each be adjusted as desired to control, for
example, the profile or density of the plasma being formed via
controlling the inductance on each coil. Each of the first and
second coils 110, 112 is coupled through a matching network 114 via
the RF feed structure 106, to the RF power supply 108. The RF power
supply 108 may illustratively be capable of producing up to about
4000 W (but not limited to about 4000 W) at a tunable frequency in
a range from 50 kHz to 13.56 MHz, although other frequencies and
powers may be provided as desired for particular applications.
[0052] In some embodiments, a power divider 105, such as a dividing
capacitor, may be provided between the RF feed structure 106 and
the RF power supply 108 to control the relative quantity of RF
power provided to the respective first and second coils. For
example, as shown in FIG. 1, the power divider 105 may be disposed
in the line coupling the RF feed structure 106 to the RF power
supply 108 for controlling the amount of RF power provided to each
coil (thereby facilitating control of plasma characteristics in
zones corresponding to the first and second coils). In some
embodiments, the power divider 105 may be incorporated into the
match network 114. In some embodiments, after the power divider
105, RF current flows to the RF feed structure 106 where it is
distributed to the first and second RF coils 110, 112.
Alternatively, the split RF current may be fed directly to each of
the respective first and second RF coils.
[0053] A heater element 121 may be disposed atop the lid 120 to
facilitate heating the interior of the process chamber 104. The
heater element 121 may be disposed between the lid 120 and the
first and second coils 110, 112. In some embodiments. the heater
element 121 may include a resistive heating element and may be
coupled to a power supply 123, such as an AC power supply,
configured to provide sufficient energy to control the temperature
of the heater element 121 to be between about 50 to about 100
degrees Celsius. In some embodiments, the heater element 121 may be
an open break heater. In some embodiments, the heater element 121
may comprise a no break heater, such as an annular element, thereby
facilitating uniform plasma formation within the process chamber
104.
[0054] During operation, the substrate 115 (such as a semiconductor
wafer or other substrate suitable for plasma processing) may be
placed on the substrate support 116 and process gases may be
supplied from a gas panel 138 through entry ports 126 to form a
gaseous mixture 150 within the process chamber 104. For example,
prior to introduction of the process gases, a temperature of
surfaces within the chamber may be controlled, for example, by the
heater 121 as discussed above to have inner volume facing surfaces
at a temperature of between about 100 to 200 degrees Celsius, or
about 150 degrees Celsius. The gaseous mixture 150 may be ignited
into a plasma 155 in the process chamber 104 by applying power from
the plasma source 108 to the first and second coils 110, 112. In
some embodiments, power from the bias source 122 may be also
provided to the substrate support 116. The pressure within the
interior of the chamber 104 may be controlled using a throttle
valve 127 and a vacuum pump 136. The temperature of the chamber
wall 130 may be controlled using liquid-containing conduits (not
shown) that run through the wall 130.
[0055] The controller 140 comprises a central processing unit (CPU)
144, a memory 142, and support circuits 146 for the CPU 144 and
facilitates control of the components of the reactor 100 and, as
such, of methods of forming a plasma, such as discussed herein. The
controller 140 may be one of any form of general-purpose computer
processor that can be used in an industrial setting for controlling
various chambers and sub-processors. The memory, or
computer-readable medium, 142 of the CPU 144 may be one or more of
readily available memory such as random access memory (RAM), read
only memory (ROM), floppy disk, hard disk, or any other form of
digital storage, local or remote. The support circuits 146 are
coupled to the CPU 144 for supporting the processor in a
conventional manner. These circuits include cache, power supplies,
clock circuits, input/output circuitry and subsystems, and the
like. The memory 142 stores software (source or object code) that
may be executed or invoked to control the operation of the reactor
100 in the manner described herein. The software routine may also
be stored and/or executed by a second CPU (not shown) that is
remotely located from the hardware being controlled by the CPU
144.
[0056] While the foregoing is directed to embodiments of the
present invention, other and further embodiments of the invention
may be devised without departing from the basic scope thereof.
* * * * *