Ex Parte Gaudet et al

Board of Patent Appeals and Interferences

Jun 4, 2010

10813390 (B.P.A.I. Jun. 4, 2010)

UNITED STATES PATENT AND TRADEMARK OFFICE
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BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
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Ex parte MARCEL GAUDET, AELAN MOSDEN, and
ROBERT J. SOAVE
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Appeal 2009-014047
Application 10/813,390
Technology Center 1700
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Decided: June 4, 2010
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Before: CATHERINE Q. TIMM, JEFFREY T. SMITH, and
JEFFREY B. ROBERTSON, Administrative Patent Judges.

TIMM, Administrative Patent Judge.

DECISION ON APPEAL
I. STATEMENT OF CASE
Appellants appeal under 35 U.S.C. § 134 from the Examiner’s
decision to reject claims 1, 3, 4, 7, 8, and 10-30. We have jurisdiction under
35 U.S.C. § 6(b).
We AFFIRM.
Appeal 2009-014047
Application 10/813,390
Appellants’ invention relates to a method for removing chamber
residue from a plasma processing system in a dry cleaning process (Spec. ¶
[0001]). Claims 1 and 29 are illustrative:
1. A method of removing fluoro-carbon polymer
chamber residue from a plasma processing system, comprising:
introducing a process gas into a process chamber of the
plasma processing system, the process gas consisting of CO,
CO2, or at least one of these molecules in combination with one
or more of H2, NH3, H2O, N2 or an inert gas;
generating a plasma from the process gas;
exposing the fluoro-carbon polymer chamber residue to
the plasma in a waferless dry cleaning process to form a volatile
reaction product from the residue, where a shield wafer is not
provided on a substrate holder of the plasma processing system
so that the substrate holder is cleaned by the waferless dry
cleaning process; and
exhausting the reaction product from the process
chamber.
29. The method of claim 1, wherein the process gas
consists of CO, CO2 or at least one of these molecules in
combination with an inert gas.
The Examiner relies upon the following evidence:
First Named Inventor Document No. Issue or Pub. Date
Moslehi
Imai
Yeh
Sieber
US 5,403,434
US 6,057,247
US 6,545,245 B2
US 7,041,608 B2
Apr. 4, 1995
May 2, 2000
Apr. 8, 2003
May 9, 2006
Suda US 2004/0109263 A1 Jun. 10, 2004
The Examiner maintains the following rejections:
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Application 10/813,390
1. The rejection of claims 1, 3, 4, 7, 8, 10-23, and 27-30 under 35 U.S.C.
§ 103(a) as unpatentable over Yeh in view of Suda and Sieber or Imai;
and
2. The rejection of claims 24-26 under 35 U.S.C. § 103(a) as
unpatentable over Yeh in view of Suda, Sieber or Imai, and Moslehi.
With respect to the first rejection, Appellants present arguments with
respect to all the rejected claims as a group (Br. 4-7), for which we select
independent claim 1 as representative. Appellants do not advance any
additional arguments for the second rejection (Br. 7). Thus, the issues
presented for both rejections are the same.
II. ISSUE ON APPEAL
A first issue on appeal arising from the contentions of Appellants and
the Examiner is: did the Examiner err in concluding that the substitution of
a known oxygen plasma source with another known oxygen plasma source
would have been obvious as it would have yielded predictable results?
A second issue is: did the Examiner err in concluding that it would
have been obvious to conduct Yeh’s process without a shield wafer?
A third issue is: have Appellants provided a showing of unexpected
results such that when all the evidence is weighed anew, it supports a
conclusion of non-obviousness?
We answer these questions in the negative.
III. FACTUAL FINDINGS
Except those findings that we expressly overturn or set aside in the
Analysis that follows, we adopt the Examiner’s findings in the Answer as
our own. Additional findings of fact may also appear in the Analysis that
follows.
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Application 10/813,390
IV. PRINCIPLES OF LAW
“The combination of familiar elements according to known methods
is likely to be obvious when it does no more than yield predictable results.”
KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 416 (2007). The question to be
asked is “whether the improvement is more than the predictable use of prior
art elements according to their established functions.” KSR, 550 U.S. at 417.
A patent applicant can rebut a prima facie case of obviousness by
showing “unexpected results,” i.e., showing that the claimed invention
possesses a superior property or advantage that a person of ordinary skill in
the art would have found surprising or unexpected. See In re Geisler, 116
F.3d 1465, 1469 (Fed. Cir. 1997) (quoting In re Soni, 54 F.3d 746, 750 (Fed.
Cir. 1995)). “[W]hen unexpected results are used as evidence of
nonobviousness, the results must be shown to be unexpected compared with
the closest prior art.” In re Baxter Travenol Labs., 952 F.2d 388, 392 (Fed.
Cir. 1991). Additionally, when the evidence directed to non-obviousness is
directed to subject matter which is narrower than the claim, Appellants have
not provided evidence of unexpected results commensurate in scope with the
claimed subject matter. See, e.g., In re Harris, 409 F.3d 1339, 1344 (Fed.
Cir. 2005) (“Even assuming that the results were unexpected, Harris needed
to show results covering the scope of the claimed range. Alternatively
Harris needed to narrow the claims.”); In re Greenfield, 571 F.2d 1185, 1189
(CCPA 1978) (“Establishing that one (or a small number of) species gives
unexpected results is inadequate proof, for ‘it is the view of this court that
objective evidence of non-obviousness must be commensurate in scope with
the claims which the evidence is offered to support.’”) (quoting In re Tiffin,
448 F.2d 791, 792 (CCPA 1971)).
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Application 10/813,390
V. ANALYSIS
Turning to the first issue, we note that the Examiner relies on the
teaching of Yeh to show that it was known in the art to clean a plasma
processing chamber using an oxygen plasma, the teaching of Suda to show
that it was known in the art to generate an oxygen plasma from a CO or CO2
source as a mere alternative to an O2 plasma source, and the teachings of
Sieber or Imai to show that it was known in the art that an oxygen plasma is
effective in removing fluoro-carbon material (Ans. 5). The Examiner
concludes that substitution of a known oxygen plasma source with another
known oxygen plasma source would have been obvious as it would have
yielded predictable results (Ans. 5).
Appellants point out differences between what each of the references
teach as compared to what is claimed, but do not specifically dispute any of
the Examiner’s specific findings. We find that the evidence as a whole
supports the Examiner’s conclusion of obviousness.
Yeh teaches that it was known in the art to use an oxygen plasma to
clean a plasma processing chamber (Yeh, col. 4, ll. 26-33). Suda teaches
that it was known in the art to alternatively use CO, CO2, or oxygen for
generating oxygen plasma (see Suda, ¶ [0082]). While Suda uses the
oxygen plasma to etch (removing material from a target) rather than to clean
(removing material from the plasma chamber), the fact remains that Suda
teaches known alternative sources for generating oxygen plasma. A person
of ordinary skill in the art would have reasonably expected that oxygen
plasma generated from any known source would have been suitable for
cleaning a plasma processing chamber. Consequently, we determine that the
evidence supports the Examiner’s obviousness determination.
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The second issue arises from Appellants’ argument that one of
ordinary skill in the art would not select the merely mentioned waferless
process of Yeh and then modify the process using parameters of Suda,
Sieber, or Imai which are not waferless processes (Br. 7). However, Yeh
teaches that the RF power applied to the second electrode should be between
2W and 6W to effectively remove the polymer build up on the substrate
holder, yet can be increased to between 100W and 250 W if a sacrificial
substrate (dummy wafer) is positioned on the substrate holder (Yeh, col. 5,
ll. 1-10). Thus, Appellants’ arguments do not refute the Examiner’s finding
that Yeh teaches that it was known in the art to use oxygen plasma to clean a
processing chamber in a waferless condition (Ans. 4).
With regard to the third issue, Appellants contend that Figures 5-7 of
Appellants’ Specification show that CO and/or CO2 process gases provide
superior results for cleaning a processing chamber (Br. 5). The Examiner
responds that the data from Appellants’ Specification is unpersuasive (Ans.
9). We agree with the Examiner that Appellants’ Specification is
unpersuasive as evidence of unexpected and superior results for using the
claimed process gas “consisting of CO, CO2, or at least one of these
molecules in combination with one or more of H2, NH3, H2O, N2 or an inert
gas” as claimed. In particular, Appellants’ data does not show a clear
advantage over the entire scope of the claimed invention. There is no data
showing an advantage using CO in combination with H2, NH3, H2O, N2 or
any inert gas other than argon, and there is no data showing any examples
using CO2 at all (see Spec. Figures 5-7). Further, Figure 6 shows better
results from using CO and oxygen (see Examples 4, 5, and 7) than using CO
and argon (see Example 3).
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Application 10/813,390
The evidence as a whole supports the Examiner’s conclusion that
using one of CO or CO2 alone or in combination with one or more of H2,
NH3, H2O, N2 or an inert gas as the source for oxygen plasma for removing
fluoro-carbon polymer residue from a waferless reaction chamber would
have been obvious to one of ordinary skill in the art based on the teachings
of Yeh, Suda, and Sieber or Imai.
VI. CLAIMS 29 AND 30
Appellants further contend that the cited prior art references do not
disclose a process gas including an inert gas, particularly argon, the subject
matter of claims 20 and 30, respectively (Br. 7). The Examiner has found
that Suda teaches using CO or CO2 with nitrogen and argon to generate
oxygen plasma (Suda, ¶ [0082]) and reasoned that “it is well known in the
art that as both nitrogen and argon are inert gases, a mixture of the two gases
substituted for one or the other also yields predictable results and is obvious”
(Ans. 11-12). Appellants fail to address the Examiner’s specific findings
and positions articulated in the Answer or explain why these positions are
deficient. A general allegation that the art does not teach a claim limitation
is no more than merely pointing out the claim limitation. 37 C.F.R.
§ 41.37(c)(1)(vii) (“A statement which merely points out what a claim
recites will not be considered an argument for separate patentability of the
claim.”). Such overarching statements fall well short of rebutting the
Examiner’s prima facie case of obviousness, a position that Appellants have
provided us no grounds to find unreasonable.
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VII. CONCLUSION
On the record before us1 and for the reasons discussed above, we
sustain the rejections maintained by the Examiner.
VIII. DECISION
We affirm the Examiner’s decision.
IX. TIME PERIOD FOR RESPONSE
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a).

AFFIRMED

ssl
OBLON, SPIVAK, MCCLELLAND MAIER & NEUSTADT, L.L.P.
1940 DUKE STREET
ALEXANDRIA, VA 22314

1 Only those arguments actually made by Appellants have been considered
in this decision. Arguments which Appellants could have made but chose
not to make have not been considered and are deemed to be waived. See 37
C.F.R. § 41.37(c)(1)(vii) (2008).
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