Ex Parte Bergman

Board of Patent Appeals and Interferences

May 23, 2007

10998278 (B.P.A.I. May. 23, 2007)

The opinion in support of the decision being entered today was not written
for publication and is not binding precedent of the Board.

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte ERIC J. BERGMAN
____________

Appeal 2007-1684
Application 10/998,278
Technology Center 1700
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Decided: May 23, 2007
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Before EDWARD C. KIMLIN, CHARLES F. WARREN, and
JEFFREY T. SMITH, Administrative Patent Judges.

KIMLIN, Administrative Patent Judge.

DECISION ON APPEAL
This is an appeal from the final rejection of claims 1-4, 7, 8, 10-15,
17, 18, 22, 26, 27, and 34-41. Claim 1 is illustrative:
1. A method for cleaning a workpiece, comprising:

placing the workpiece into a chamber;

directly or indirectly heating the workpiece,

Appeal 2007-1684
Application 10/998,278

providing water vapor into the chamber, with the water vapor
exceeding about 100 C;

providing ozone gas into the chamber;

pressurizing the chamber to an above ambient pressure to increase
ozone gas concentration in the chamber, and with the ozone gas reacting
with a contaminant on the workpiec4e to clean the workpiece.

The Examiner relies upon the following reference as evidence of
obviousness:
DeGendt US 6,551,409 B1 Apr. 22, 2003
Appellant's claimed invention is directed to a method for cleaning a
workpiece, just as a wafer. The method entails placing the workpiece in a
chamber, heating the workpiece, providing water vapor and ozone gas into
the chamber, and pressurizing the chamber to an above ambient pressure to
increase the ozone gas concentration in the chamber.
All the appealed claims stand rejected under 35 U.S.C. § 103(a) as
being unpatentable over DeGendt.
With the exception of claims 26 and 40, and claim 41, Appellant does
not set forth separate arguments for the claims on appeal. Accordingly, with
the noted exceptions, all the appealed claims stand or fall together with
claim 1.
We have thoroughly reviewed each of Appellant's arguments for
patentability. However, we are convinced that the Examiner has drawn the
proper legal conclusion that the claimed subject matter would have been
obvious to one of ordinary skill in the art within the meaning of § 103 in
view of the applied prior art. Accordingly, we will sustain the Examiner's
rejection for essentially those reasons expressed in the Answer.
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Application 10/998,278

Appellant does not dispute the Examiner's factual determination that
DeGendt, like Appellant, discloses a method for cleaning a workpiece, such
as a wafer, comprising the steps of heating the workpiece, providing water
vapor and ozone gas into the chamber and effecting a reaction between the
ozone gas and contaminants to clean the workpiece. It is Appellant's
principal contention that DeGendt provides no teaching or suggestion of
pressurizing the chamber to an above ambient pressure. According to
Appellant, "there is no recognition of use of above ambient pressure in
processing" (Br. 4, second para.).
We do not subscribe to Appellant's position. As pointed out by the
Examiner, the claim 1 recitation "pressurizing the chamber to an above
ambient pressure" encompasses or embraces chamber pressures of only
slightly greater than ambient and, thereby, provides no patentable distinction
over the DeGendt disclosure that "[t]he pressure conditions in the tank are
about atmospheric conditions" (col. 5, ll. 35-36, emphases added). It can not
be gainsaid that there is no meaningful distinction between the "about
atmospheric" pressure of DeGendt, which would include, for example, 1.1
atmospheres, and the presently claimed "above ambient pressure," which
would also include 1.1 atmospheres.
Also, we find no error in the Examiner's reasoning that the elevated
temperatures disclosed by DeGendt would necessarily result in a chamber
pressure in excess of atmospheric pressure. DeGendt expressly teaches that
"high temperature results in more efficient cleaning" (col. 7, ll. 34-35), and it
is fundamental that an increase in temperature of a sealed chamber, such as
the one admittedly disclosed by DeGendt, necessarily results in an increase
in pressure. Also, like Appellant, DeGendt teaches that an increase in ozone
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Application 10/998,278

concentration near the surface of the wafer results in a better cleaning
efficiency at elevated temperatures (col. 7, ll. 13-16), which teaching
corresponds to the claimed step of pressurizing the chamber to increase the
ozone gas concentration. Manifestly, one of ordinary skill in the art would
have understood that increasing the concentration of the ozone in the
chamber results in an increase in the chamber pressure, and that an obvious
way to increase the concentration is to increase the pressure of the ozone.
Appellant cites an article by Gale et al. “to demonstrate how the
claimed invention is viewed by others in the field”, and how the effective
pressure is described at page 2 of the article, last paragraph (see Br. 5,
second para.). However, the elevated pressures discussed in the art are not
recited in the appealed claims and, therefore, Appellant's argument is not
germane to the claimed subject matter.
Appellant also cites paragraphs [0047] and [0061] in the present
Specification as demonstrating unexpected results. However, the referenced
paragraphs of the Specification are hardly commensurate in scope with the
degree of protection sought by the appealed claims, which set no limit on the
minimum amount of pressure above atmospheric. See In re Grasselli,
713 F.2d 731, 742, 218 USPQ 769, 778 (Fed. Cir. 1983); In re Clemens,
622 F.2d 1029, 1035, 206 USPQ 289, 296 (CCPA 1980). Also, we note that
Specification paragraph [0047] makes no mention of chamber pressure,
whereas paragraph [0061] speaks of using steam at 15 psi and 126ºC but
does not specify the pressure maintained in the chamber during the cleaning
process.
Regarding the claim 26 recitation of maintaining the surface of the
wafer at a temperature below the temperature of the water vapor in the
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Application 10/998,278

chamber, we fully concur with the Examiner that such is implicit in the
DeGendt disclosure of forming a thin condensation layer on the wafer.
Certainly, maintaining the surface of the wafer at a temperature lower than
the temperature of the water vapor would have been an obvious way of
forming the condensation layer on the wafer described by DeGendt. As for
separately argued claim 41, we are in full agreement with the Examiner that
spraying the steam into the chamber would have been an obvious way of
providing steam in the process of DeGendt. We observe that Appellant
bases no argument upon objective evidence of nonobviousness with respect
to separately argued claims 26, 40, and 41.
In conclusion, based on the foregoing and the reasons well-stated by
the Examiner, the Examiner's decision rejecting the appealed claims 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)(iv)(2006).
AFFIRMED

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