Ex Parte Schauer et al

Patent Trial and Appeal Board

Feb 8, 2018

12892201 (P.T.A.B. Feb. 8, 2018)

United States Patent and Trademark Office
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O.Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
12/892,201 09/28/2010 Reinhard Schauer WSAG0211PUS1 1820
22045 7590 02/12/2018
RROOKS KTTSHMAN P C
EXAMINER
1000 TOWN CENTER NUCKOLS, TIFFANY Z
TWENTY-SECOND FLOOR
SOUTHFIELD, MI 48075 ART UNIT PAPER NUMBER
1716
NOTIFICATION DATE DELIVERY MODE
02/12/2018 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
docketing @brookskushman. com
kdilucia@brookskushman.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte REINHARD SCHAUER and NORBERT WERNER
Appeal 2017-005206
Application 12/892,2011
Technology Center 1700
Before ROMULO H. DELMENDO, KAREN M. HASTINGS, and
JAMES C. HOUSEL, Administrative Patent Judges.
PER CURIAM.
DECISION ON APPEAL
Appellants seek our review under 35 U.S.C. § 134(a) of the
Examiner’s decision rejecting claims 29-47.
We have jurisdiction over the appeal under 35 U.S.C. § 6(b).
We AFFIRM.
1 Appellants identify the real party in interest as Siltronic AG (Appeal Br. 3).
Appeal 2017-005206
Application 12/892,201
Independent claim 29 is illustrative of the subject matter on appeal
(emphases added):
29. A device for supporting a semiconductor wafer during
the deposition of a layer on a front side of the semiconductor
wafer by chemical vapor deposition in a deposition reactor, the
semiconductor wafer having a front side, a backside, and an
edge, the device comprising:
a susceptor having a continuous top surface extending
below the entire backside of the semiconductor wafer, the
susceptor being constructed of a porous material
a wafer support ring having a thermal conductivity of
from 5 W/mK to 100 W/mK, resting directly and firmly on the
susceptor such that deposition gas is prevented from passing
between the ring and the susceptor into a generally closed space
defined by the backside of the wafer, the support ring, and the
continuous top surface of the susceptor, the ring further acting
as a thermal buffer between the susceptor and a supported
semiconductor wafer, the ring, having a thickness of 0.5-1.5
mm, positioned between the semiconductor wafer and the
susceptor such that the backside of the wafer does not contact
the susceptor,
wherein the ring has a continuous annular recess for
receiving the semiconductor wafer, the recess having an outer
diameter and an inner diameter, the recess having a width of 5 -
15 mm in the direction of its inner diameter, and a depth of
from 0.3 mm to 0.7 mm, the inner diameter being less than the
diameter of the semiconductor wafer to be received in the ring
and an outer diameter greater than the diameter of the
semiconductor wafer.
The Examiner maintains the following rejections:2
(a) claims 29—35, 37—39, and 41—47 under 35 U.S.C. § 103(a) as
being unpatentable over Sato et al., (US 5,474,612 A, issued Dec. 12, 1995)
2 We refer to the Specification, filed Sept. 28, 2010 (“Spec.”); Appeal Brief,
filed July 15, 2016 (“Appeal Br.”); Examiner’s Answer, mailed Dec. 21,
2016 (“Ans.”); and the Reply Brief, filed Feb. 15, 2017 (“Reply Br.”).
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Application 12/892,201
(“Sato”) in view of Moto et al., (US 6,167,194 A, issued Dec. 26, 2000)
(“Moto”), Schauer et al., (US 7,101,794 B2, issued Sept. 5, 2006)
(“Schauer”), and Yang et al., (US 6,444,027 Bl, issued Sept. 3, 2002)
(“Yang”);
(b) claim 36 under 35 U.S.C. § 103(a) as being unpatentable over
Sato, Moto, Schauer, and Yang and further in view of Hwang et al., (US
2006/0004493 Al, published Jan. 5, 2006) (“Hwang”);
(c) claim 40 under 35 U.S.C. § 103(a) as being unpatentable over
Sato, Moto, Schauer, and Yang and further in view of Ries et al., (US
6,596,095 B2, issued July 22, 2003) (“Ries ’095”);
(d) claims 29—35, 42, 43, 45, and 46 under 35 U.S.C. § 103(a) as
being unpatentable over Ries et al., (US 2001/0037761 Al, published Nov.
8, 2001) (“Ries ’761”) in view of Moto and Sato; and
(e) claim 36 under 35 U.S.C. § 103(a) as being unpatentable over
Ries ’761 in view of Moto and Sato and further in view of Hwang.
ANALYSIS
The § 103(a) rejection over Sato, Moto, Schauer, and Yang
Claims 29—35, 37—39, and 41—47 under 35 U.S.C. § 103(a) as being
unpatentable over Sato, Moto, Schauer, and Yang. Appellants argue claims
29-35, 37—39, 41, 42, and 44-46 as a first group, claim 43 as a second
group, and claim 47 as a third group (Appeal Br. 5—26). We address these
groups separately below.
Claims 29-35. 37-39. 41. 42. and 4U46
We select claim 29 as representative. 37 C.F.R. § 41.37(c)(l)(iv).
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Appellants contend3 that the embodiment depicted in Figure 26 of
Sato relates to the use of a substrate-supporting member (i.e., second
member) that has a low thermal conductivity (e.g., a disc made of glass or
ceramic) or has a lower thermal conductivity than a susceptor (i.e., first
member) so the substrate-supporting member minimizes heat flow from the
susceptor to the periphery of a wafer (Appeal Br. 7—10; Reply Br. 2—5).
Appellants assert that some glasses, such as fused silica, have thermal
conductivities lower than the range recited in claim 29, Sato teaches away
from a wafer support ring having the thermal conductivity recited in claim
29, the Examiner has not properly articulated a reason to change the
materials used by Sato, and there is no evidence to support such a conclusion
(Appeal Br. 10-11).
Appellants’ arguments are unpersuasive. In the rejection of claim 29,
the Examiner finds Sato discloses a device for supporting a semiconductor
wafer 3, the device including a susceptor 4 and a wafer support ring 10 that
includes a continuous annular recess on which the wafer 3 rests, citing
Figure 26 of Sato (Ans. 5—6). Sato discloses a holder 4, a substrate
supporting member 10 having a stepped portion upon which a substrate 3 is
supported, and that “the member 10 is made of glass or ceramics, either
being material having low thermal conductivity” (Sato 14:15—28).
3 Appellants argue that they discovered an unexpected result and assert that
the invention satisfies a long felt need (Appeal Br. 6—7). Appellants do not
cite any evidence supporting either assertion, which are made in the context
of what appears to be a summary of forthcoming arguments. Therefore, we
do not treat these arguments as assertions of secondary indicia of
nonobviousness. To the extent such arguments can be treated as assertions
of secondary indicia, they are entitled to little weight given the lack of
citations to supporting evidence.
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Sato’s disclosure of “glass or ceramics . . . having low thermal
conductivity” encompasses various materials that can be used for the
substrate-supporting member. Although Appellants assert some glasses
would fall outside the claimed thermal conductivity range recited in claim
29, it is reasonable that some glass or ceramic materials would fall within
the range, especially when one considers that thermal conductivity varies
with temperature and claim 29 does not specify a temperature for the
claimed thermal conductivity range so as to further limit the materials that
fall within its scope.
To the extent the Examiner relies upon the embodiment depicted in
Figure 14 of Sato, Sato discloses that embodiment includes a block 4 (i.e.,
susceptor), an annular wall 11, and a substrate-supporting member 10 (Sato
10:13—20). Thus, the embodiment of Figure 14 also provides the structures
recited in claim 29. Sato discloses “the substrate-supporting member 10 is
made of material having substantially the same heat capacity per unit area as
that of the substrate 3” {id. 10:51—54). Although Sato discloses such a
member 10 can be made of silicon {id. 11:10-15), Moto discloses a guard
ring 10 for supporting a semiconductor wafer and that the guard ring 10 can
be made of a material having the same specific heat as the semiconductor
wafer, such as silicon carbide (Moto 5:38-40, 6:1—5). Therefore, in addition
to the discussion above regarding the embodiment of Figure 26 of Sato, the
applied references also demonstrate it was known to use a material having
the thermal conductivity of claim 29, as well as the specific material recited
in dependent claim 30.
Appellants argue that the various embodiments of Sato are separate,
unrelated disclosures directed to different solutions and it would not have
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been obvious to modify one embodiment, such as the embodiment depicted
in Figure 26, in view of another embodiment, such as the embodiment
depicted in Figure 14 of Sato (Appeal Br. 7—8, 11; Reply Br. 2-4).
However, any combination or substitution of the embodiments of Sato relied
upon by the Examiner regards the use of prior art elements (i.e., substrate­
supporting members 10) according to their established functions (i.e., to
support a semiconductor substrate) (see KSR Int’l Co. v. Teleflex Inc., 550
U.S. 398, 417 (2007)).
In view of the discussion above regarding the embodiments of Figures
26 and 14 of Sato, the disclosure of Yang is not required to demonstrate the
use of a material for a substrate-supporting member 10 having the thermal
conductivity recited in claim 29. However, to the extent the Examiner relies
upon the disclosure of Yang, such as for dependent claim 31, Yang
demonstrates it was known to support a semiconductor wafer with a
structure made of graphite coated with silicon carbide (Yang 4:38—65, 5:56—
61). In other words, although Yang does not disclose the use of a ring
separate from a susceptor, Yang demonstrates it was known to support a
semiconductor wafer with a material having the thermal conductivity recited
in claim 29. Using such a material for the member 10 of Sato would have
involved the use of known elements according to their established functions
(KSR, 550 U.S. at 417). Furthermore, the susceptor of Yang functions as a
combined or integral susceptor and ring, as stated by the Examiner (Ans.
48). Sato discloses that such a combined or integral susceptor and ring can
be used for its device (Sato 8:26—30, Figure 4) or that separate susceptors
and rings can be used (id. at Figures 14, 26).
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Appellants contend that Schauer teaches away from the susceptor of
Yang because its susceptor includes holes that would cause localized
temperature differences and that Sato teaches away from the stepped
susceptor of Yang and its use of a material that is not a low conductivity
material (Appeal Br. 18—20; Reply Br. 7). Further, Appellants assert that
Yang does not disclose a support ring as a separate structure from a
susceptor (Appeal Br. 19). However, Yang is not cited for its disclosure of a
susceptor with holes. Appellants’ argument amounts to a bodily
incorporation of the structure disclosed by Yang into the device of Sato.
“The test for obviousness is not whether the features of a secondary
reference may be bodily incorporated into the structure of the primary
reference. . . . Rather, the test is what the combined teachings of those
references would have suggested to those of ordinary skill in the art.” (see In
re Keller, 642 F.2d 413, 425 (CCPA 1981) (citations omitted)). As
discussed above, the disclosure of Yang demonstrates a structure made of
silicon carbide coated graphite can be used to support a semiconductor
wafer. With respect to Sato’s disclosure of a “low conductivity material,”
Sato discloses such a material can be a “ceramic” (Sato 14:24—26), which
encompasses graphite coated with silicon carbide. Therefore, Appellants’
arguments are unpersuasive.
Appellants also argue there is no evidence in the record, other than in
Appellants’ disclosure, that there was a dislocation problem for reactors
having a susceptor that extends below the entirety of a wafer surface and is
radiatively heated above and below (Appeal Br. 11). The problem faced by
an applicant is a relevant factor to take into consideration in an obviousness
determination. However, an invention may be obvious for reasons the
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inventor did not contemplate. See In re Dillon, 919 F.2d 688, 693 (Fed. Cir.
1990) (en banc) (“In particular, the statement [in In re Wright] that a prima
facie obviousness rejection is not supported if no reference shows or
suggests the newly-discovered properties and results of a claimed structure
is not the law.”) (overruling-in-part In re Wright, 848 F.2d 1216 (Fed. Cir.
1988)). Furthermore, “the motivation in the prior art to combine the
references does not have to be identical to that of the applicant to establish
obviousness.” In re Kemps, 97 F.3d 1427, 1430 (Fed. Cir. 1996). As we
found above, Appellants do not direct us to objective evidence of any
secondary considerations, such as unexpected results, in support of
nonobviousness. Dillon, 919 F.2d at 692 (explaining that where the prior art
gives reason or motivation to make the claimed invention, the burden and
opportunity to produce evidence such as unexpected results then falls on an
applicant to rebut that prima facie case).
With regard to Moto, Appellants argue that the extension 13a of
Moto’s guard ring is only 2 mm wide and is tapered to minimize a contact
surface and heat conduction between the guard ring and the wafer and
therefore one of ordinary skill in the art would have lacked a reason to
modify a supporting ledge of a wafer support ring to be 5—15 mm wide, as
recited in claim 29 (Appeal Br. 14—17; Reply Br. 6—7).
Appellants’ arguments are unpersuasive. The Examiner finds that
Moto discloses a wafer support ring having a thickness of 0.8 mm, a recess
depth of 0.8 mm, and a recess width of 2 mm (Ans. 6). Moto discloses the
thickness of the main part 11 of its guard ring 10 is 0.8 mm “and is equal to
the thickness of the semiconductor wafer W” (Moto 6:9—11). Moto
discloses that the height of the ring recess 12 “is 0.8 mm and is therefore
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Application 12/892,201
identical to the thickness of the semiconductor wafer W” (id. 6:23—25).
Moto further discloses that the substrate bearing part 13 of the ring 10 “has a
width of roughly 2 mm and is made annular” (id. 6:48—51). Therefore, the
disclosure of Moto supports the Examiner’s findings.
To the extent the ring dimensions do not fall within the ranges recited
in claim 29, the Examiner concludes it would have been obvious to modify
the ring dimensions disclosed by Moto to obtain their workable or optimal
values (Ans. 6—7). As noted above, Moto discloses that dimensions of its
ring are related to dimensions of the wafer it supports. Therefore, it would
have been obvious to modify the dimensions of a wafer support ring to
determine its workable or optimal dimensions, particularly when the
dimensions of a wafer are altered. Furthermore, the relationship between
ring dimensions and wafer dimensions demonstrates that the latter is a
result-effective variable. “[Discovery of an optimum value of a result
effective variable in a known process is ordinarily within the skill of the art.”
In re Boesch, 617 F.2d 272, 276 (CCPA 1980).
As argued by Appellants, Moto discloses that the surface of its
substrate bearing part 13 is tapered so there is linear contact between the
bearing part and a wafer, which makes heat conduction between the wafer
and the ring small (Moto 6:32 41). However, this does not mean that the
width of the bearing part is less, which Moto discloses as roughly 2 mm, but
only that the bearing part is tapered to minimize contact. Thus, the bearing
part may be wider or more narrow but tapered and comply with Moto’s
teachings about contact area and heat conduction. Moreover, claim 29
recites “wherein the ring has a continuous annular recess for receiving the
semiconductor wafer” (emphasis added). Even if the ring of Sato were
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modified in view of Moto to include a taper to minimize contact, the ring
would still be capable of “receiving” a semiconductor wafer, as recited in
claim 29. Appellants argue that the ring of Moto has a different function
than the ring of Sato because the ring of Moto does not lie on a susceptor
(Appeal Br. 14). However, the rings of Sato and Moto both function to
support a semiconductor wafer and both rings function to affect the transfer
ofheattothe wafer (Sato 10:13—22, 11:10-15; Moto 5:38-40, 7:22—30).
Appellants further contend there would have been no reason to modify
Sato in view of Moto because Moto discloses an epitaxial process using a
top heater and no susceptor but Sato discloses a process using heating from
below (Appeal Br. 11—12; Reply Br. 5—7). Appellants further assert that
Moto uses an optical pyrometer to detect wafer temperature and control its
top heater but this technique cannot be used in Sato, which uses a bottom
heater (Appeal Br. 12). In view of these arguments, Appellants contend the
Examiner has impermissibly engaged in picking and choosing from the
disclosure of Moto to the exclusion of other parts necessary for full
appreciation of what a reference suggests to one of ordinary skill in the art
and the Examiner has engaged in impermissible hindsight in rejecting Sato
in view of Moto and the other applied references (Appeal Br. 12—14; Reply
Br. 5-6).
Appellants’ arguments are unpersuasive. The disclosure of Sato is not
limited to only bottom heating because Sato discloses embodiments
including heating above and below a substrate (Sato Figure 39; Ans. 33).
Moreover, Appellants’ arguments regarding the pyrometer of Moto regard
the bodily incorporation of structures disclosed by Moto into Sato’s device,
not the exclusion of parts necessary for full appreciation of Moto’s
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disclosure regarding guard ring dimensions for supporting a wafer. As
discussed above, the test for obviousness is what the combined teachings of
the applied references would have suggested to one of ordinary skill in the
art {In re Keller, 642 F.2d at 425). Moto’s disclosures regarding the
dimensions for guard ring are applicable to the member 10 of Sato and its
recess, which is used for the same function of supporting a semiconductor
wafer. Moreover, Sato discloses various types of heating for processes using
its device, including top and bottom heating, and thus Sato appears to permit
the type of heating contemplated by Moto.
With regard to Schauer, Appellants assert one of ordinary skill in the
art would have lacked a reason to modify Sato, as modified by Moto, in
view of Schauer because the porous susceptor of Schauer would have a
lower thermal conductivity and would not be useful or effective in the
process of Sato, which relies upon bottom heating of its susceptor so heat is
conducted through the susceptor and radiated to a wafer (Appeal Br. 17—
18).4 This argument is unpersuasive. As stated by the Examiner (Ans. 47),
Appellants do not cite any evidence to support this argument. Further, there
is no evidence that Appellants’ comparison of glass and fiberglass would
4 Appellants assert an unexpected result, citing page 8, lines 16—21, of their
Specification. However, the cited passage of the Specification only
describes an advantage for their invention and does not describe the result as
unexpected or provide evidence of any unexpected result. Therefore, we do
not treat these arguments as assertions of secondary indicia of
nonobviousness. To the extent such arguments can be treated as assertions
of secondary indicia, they are entitled to little weight given the lack of
citations to supporting evidence. In re Lindner, 457 F.2d 506, 508 (CCPA
1972) (“[M]ere conclusory statements in the specification and affidavits are
entitled to little weight when the Patent Office questions the efficacy of
those statements.”).
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apply to graphite and result in a lower thermal conductivity by orders of
magnitude or a thermal conductivity that would be unsuitable for Sato’s
process (Appeal Br. 17—18). As the Examiner finds (Ans. 47), Schauer
discloses its susceptor can be used in vapor deposition processes (Schauer
1:14—21). Therefore, Schauer would have suggested that its porous
susceptor is useful for processes contemplated by Sato.
In addition, Appellants contend “that in many of the embodiments of
Sato, the space between the wafer and susceptor is not isolated from the
reactor interior, e.g. is not a ‘closed’ space” and the posts or other structures
of Sato do not prevent deposition gas from passing into a closed space
between the backside of a wafer, a support ring, and a top surface of a
susceptor, as recited in claim 29 (Appeal Br. 18).
This argument is not persuasive. The Examiner finds that although
Sato does not expressly disclose the prevention of gas flow recited in claim
29, Sato, as modified by the applied references, discloses substantially the
same structure recited in claim 29 and therefore necessarily performs the
recited gas flow prevention function (Ans. 8—9). The structure depicted in
Figure 26 supports this finding by showing a cross section of the annular
member 10 positioned between the substrate 3 and holder 4. Moreover, Sato
discloses “[tjhere are no gaps between the substrate 3 and the member 10,
thus not allowing the feed gas flow into the space between the holder 4 and
the lower surface of the substrate 3” with respect to the embodiment of
Figure 25 (Sato 14:4—8) and therefore demonstrates gas flow can be
prevented with its embodiments. In addition, to the extent Figure 14 is
relied upon in the Examiner’s rejection, Sato discloses this embodiment
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includes an “annular wall 11,” not posts, and Sato discloses that such an
annular wall may be substituted for posts (Sato 7:29-36, 10:15—18).
Appellants present new arguments for claims 37 and 38 at page 4 of
the Reply Brief. Appellants have not shown good cause why these
arguments could not have been presented in the Appeal Brief. Therefore, we
will not consider the separate arguments for claims 37 and 38 newly raised
in the Reply Brief. 37 C.F.R. § 41.41(b)(2).
As a result, a preponderance of the evidence in the record supports the
Examiner’s rejection of claim 29. Appellants’ arguments do not identify a
reversible error in the Examiner’s rejection of claim 29. Appellants do not
argue claims 30—35, 37—39, 41, 42, and 44-46 separately from claim 29
(Appeal Br. 5—20).
Claim 43
Claim 43 depends from claim 29 and further recites “wherein the
wafer support ring has an outer diameter of a few mm greater than an outer
diameter of the susceptor.”
The Examiner finds Figure 4 of Sato depicts a ring having an outer
diameter that is larger than the susceptor portion (Ans. 13). The Examiner
concludes it would have been obvious to use the configuration shown in
Figure 4 of Sato to modify the embodiment depicted in Figure 26 of Sato as
an equivalent means for a susceptor and wafer support ring (id. ).
Appellants argue that Figure 4 depicts a one piece, integral susceptor
in which the lower portion has the same diameter as the upper portion
(Appeal Br. 21). However, Figure 4 also depicts portion 11 as having a
smaller diameter than that of the holder 4. Thus, Figure 4 supports the
Examiner’s findings. Moreover, it would have been obvious to modify the
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embodiment of Figure 26 in view of the embodiment of Figure 4 as both
embodiments are used for the purpose of supporting a semiconductor wafer
and thus are equivalents for that purpose. Indeed, Sato discloses that the
heat path from the holder 4 to the substrate 3 in Figure 4 permits a
“negligibly small” amount of heat to be conducted (Sato 8:32—37), which
corresponds with Sato’s disclosure regarding the embodiment of Figure 26
{id. 14:15—28). As a result, Appellants’ arguments are unpersuasive.
Claim 47
Independent claim 47 recites, among other things, a device for
supporting a semiconductor wafer, the device comprising a susceptor and a
wafer support ring. Claim 47 recites “wherein the device is positioned
within an epitaxy chamber having upper heating elements configured to heat
a wafer received within the support ring from above, and lower heating
elements configured to heat the susceptor from below.”
The Examiner finds that claim 47 does not positively recite the
chamber or the heating elements referenced in the above quoted language
(Ans. 18—19). Appellants assert this language cannot be ignored and claim
47 requires these structures (Appeal Br. 21).
Even assuming Appellants’ arguments are correct, Sato discloses its
device can be used with a chamber having upper and lower heating
elements, as recited in claim 47 (Sato Figure 39). Figure 3 of Yang also
demonstrates it was known to use wafer support devices in reactor chambers
having upper and lower heaters.
For the reasons discussed above and those set forth in the Examiner’s
Answer, we sustain the Examiner’s § 103(a) rejection of claims 29-35, 37—
39, and 41—47 over Sato, Moto, Schauer, and Yang.
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The § 103(a) rejection over Sato, Moto, Schauer, Yang, and Hwang
Claim 36 is rejected under 35 U.S.C. § 103(a) as being unpatentable
over Sato, Moto, Schauer, and Yang and further in view of Hwang.
Appellants do not present any arguments for this rejection. Therefore, we
sustain the Examiner’s § 103(a) rejection of claim 36 over Sato, Moto,
Schauer, and Yang and Hwang.
The § 103(a) rejection over Sato, Moto, Schauer, Yang, and Ries ’095
Claim 40 is rejected under 35 U.S.C. § 103(a) as being unpatentable
over Sato, Moto, Schauer, and Yang and further in view of Ries ’095. Claim
40 depends from claim 39, which depends from claim 29, and further recites
“the porous susceptor has pores in the form of a multiplicity of small bores
spaced apart on the entire continuous top surface of the susceptor which lies
below the wafer.”
Appellants state that Ries ’095 “does indeed (as also does Yang),
disclose a susceptor with a multiplicity of holes” but it would not have been
obvious to modify Sato (as modified by Moto, Schauer, and Yang) in view
of Ries ’095 because Schauer discloses problems with susceptors having
holes (Appeal Br. 22).
Appellants’ arguments are unpersuasive. Schauer discloses that
susceptors with holes can create an adverse effect on nanotopography of the
wafer if the diameter of the holes exceed a certain size (Schauer 1:65—2:4).
However, Ries ’095 discloses that susceptors with its perforations eliminate
halo and reduce nanotopography (Ries ’095 17:19-46, 55—58). Thus, Ries
’095 addresses the very problems with which Schauer is concerned.
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Appellants also argue that Sato teaches away from a stepped integral
susceptor because the susceptor causes the wafer to be heated more at its
periphery and “[consequently, it is very difficult to form a crystal film
having a uniform thickness, on the substrate” (Appeal Br. 19-20, 22
(quoting Sato 1:41—50)). This disclosure of Sato does not teach away from a
stepped susceptor but demonstrates it is possible to use one for crystal film
growth, even it if “it is very difficult.” Something that is known or obvious
does not become patentable simply because it has been described as
somewhat inferior to some other product for the same use. In re Gurley, 27
F.3d 551, 553 (Fed. Cir. 1994).
For the reasons discussed above and those set forth in the Examiner’s
Answer, we sustain the Examiner’s § 103(a) rejection of claim 40 over Sato,
Moto, Schauer, and Yang and Ries ’095.
The § 103(a) rejection over Ries ‘761, Sato, and Moto
Claims 29-35, 42, 43, 45, and 46 are rejected under 35 U.S.C.
§ 103(a) as being unpatentable over Ries ’761 in view of Moto and Sato.
Appellants contend that Ries ’761 discloses an integral susceptor, not
a separate wafer support ring, and that Sato teaches away from such
susceptors (Appeal Br. 22—25). As discussed above, Sato’s disclosure of
difficulties with such susceptors may demonstrate their inferiority but this
does not arise to a disclosure that teaches away from their use or that they
are incapable of being used in a process for coating a semiconductor wafer
supported by the susceptor.
Appellants further argue there would not have been a reason to
modify Ries ’761 in view of Moto because Moto does not use a susceptor
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and Moto is directed to reactors with problems related to top heated reactors
(id. at 23—24). This argument regards the bodily incorporation of structures
disclosed by Moto into the device of Ries ’761, not the exclusion of parts
necessary for full appreciation of Moto’s disclosure regarding guard ring
dimensions for supporting a wafer. As discussed above, the test for
obviousness is what the combined teachings of the applied references would
have suggested to one of ordinary skill in the art. Moto’s disclosures
regarding the dimensions for guard ring are applicable to the device of Ries
’761, which is used for the same function of supporting a semiconductor
wafer. Moreover, Figure 4 of Ries ’761 includes both top and bottom
heating and thus permits the type of heating contemplated by Moto.
Appellants contend there would not have been a reason to modify
Ries ’761 in view of Sato because Sato is directed to problems related to
bottom heated reactors (id. at 24—25). This argument is unpersuasive
because both references contemplate reactors having top and bottom heating,
as demonstrated by Figure 4 of Ries ’761 and Figure 39 of Sato.
Appellants further argue there would not have been a reason to use the
embodiments of Sato in the device of Ries ’761 because Sato is directed to
low conductivity materials, “not the high conductivity support ring as
claimed by Appellants” (Appeal Br. 24). As discussed above with regard to
the rejection of claim 29 over Sato, Moto, Schauer, and Yang, Sato
exemplifies various materials that can be used for the substrate-supporting
member and it is reasonable that various known glass or ceramic materials
would fall within the thermal conductivity range recited in claim 29.
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Appeal 2017-005206
Application 12/892,201
For the reasons discussed above and those set forth in the Examiner’s
Answer, we sustain the Examiner’s § 103(a) rejection of claims 29-35, 42,
43, 45, and 46 over Ries ’761, Moto, and Sato.
The § 103(a) rejection over Ries ’761, Sato, Moto, and Hwang
Claim 36 is rejected under 35 U.S.C. § 103(a) as being unpatentable
over Ries ’761 in view of Moto and Sato and further in view of Hwang.
Appellants assert that Hwang, like Moto, is directed to top heating
without a susceptor with temperature measurement from below (Appeal Br.
26). As discussed above with regard to the previous rejection and the
arguments directed to Moto, this argument regards the bodily incorporation
of structures disclosed by Hwang into the device of Ries ’761, specifically
the top heater and temperature sensor of Hwang, not the exclusion of parts
necessary for full appreciation of Hwang’s disclosure regarding the
dimensions of an edge support 120 that functions to support a wafer (Hwang
113). Both Ries ’761 and Hwang concern structures for supporting a
semiconductor wafer and thus one of ordinary skill in the art would have
considered Hwang’s disclosure of edge support dimensions when
considering modifications to the device of Ries ’761, particularly when Ries
’761 has been modified in view of Sato to use a separate ring to support a
wafer.
For these reasons and those set forth in the Examiner’s Answer, we
sustain the Examiner’s § 103(a) rejection of claim 36 over Ries ’761, Moto,
Sato, and Hwang.
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Appeal 2017-005206
Application 12/892,201
DECISION
The Examiner’s rejection of claims 29-47 is affirmed.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(1).
AFFIRMED
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