Ex parte Frutiger

Board of Patent Appeals and Interferences

Aug 15, 2001

08481593 (B.P.A.I. Aug. 15, 2001)

The opinion in support of the decision being entered today was not written for
publication and is not binding precedent of the Board.
Paper No. 32
UNITED STATES PATENT AND TRADEMARK OFFICE
____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________
Ex parte WILLIAM A. FRUTIGER
____________
Appeal No. 1999-1451
Application No. 08/481,593
____________
ON BRIEF
____________
Before JERRY SMITH, RUGGIERO, and DIXON, Administrative Patent Judges.
DIXON, Administrative Patent Judge.
DECISION ON APPEAL
This is a decision on appeal from the examiner's final rejection of claims 1-3, 5-15, 17-
22, and 61-66. Claims 4 and 16 are objected to as dependent on rejected parent claims
and would be allowable if rewritten in independent form. These are all of the claims
pending in this application.
We REVERSE.
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Application No. 08/481,593
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BACKGROUND
The appellant's invention relates to an electrostatic wafer clamp. An understanding of
the invention can be derived from a reading of exemplary claim 1, which is reproduced
below.
1. Apparatus for electrostatic clamping of a workpiece, comprising:
a platen including at least three platen sections, said at least three platen sections
comprising a conductive material and being electrically isolated from each other;
a dielectric material disposed on said at least three platen sections, said dielectric
materials having a clamping surface for receiving a workpiece; and
means for applying a polyphase clamping voltage to said platen, said at least three
platen sections being connected to different phases of said polyphase clamping voltage
so that the workpiece is electrostatically clamped in a fixed position on said clamping
surface by electrostatic force between the workpiece and said platen sections, said
electrostatic clamping apparatus being operable to clamp the workpiece to said clamping
surface in vacuum.
The prior art references of record relied upon by the examiner in rejecting the appealed
claims are:
Klass et al. (Klass) 3,197,682 Jul. 27, 1965
Briglia 4,184,188 Jan. 15, 1980
Lewin 4,554,611 Nov. 19, 1985
Claims 1, 2, 7-14, 19-22, and 61-66 stand rejected under 35 U.S.C. § 103 as being
unpatentable over Klass. Claims 3 and 15 stand rejected under 35 U.S.C. § 103 as being
Appeal No. 1999-1451
Application No. 08/481,593
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unpatentable over Klass in view of Lewin. Claims 5, 6, 17, and 18 stand rejected under 35
U.S.C. § 103 as being unpatentable over Klass in view of Briglia.
Rather than reiterate the conflicting viewpoints advanced by the examiner and the
appellant regarding the above-noted rejections, we make reference to the Office action
setting forth the rejection (Paper No. 15, mailed June 23, 1997) and the examiner's
answer (Paper No. 24, mailed Aug. 4, 1998) for the examiner's reasoning in support of the
rejections, and to the appellant's brief (Paper No. 23, filed Jun. 15, 1998) and reply brief
(Paper No. 26, filed Oct. 8, 1998) for the appellant's arguments thereagainst.
OPINION
In reaching our decision in this appeal, we have given careful consideration to the
appellant's specification and claims, to the applied prior art references, and to the
respective positions articulated by the appellant and the examiner. As a consequence of
our review, we make the determinations which follow.
At the outset we note that the examiner has repeatedly referenced many of the Office
actions throughout the answer. Rather than remand this case for a proper statement of the
rejection and answer to the arguments in a single document, we have referenced the
prosecution history as the examiner has argued through the answer, and we find that
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Application No. 08/481,593
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throughout the prosecution history, the examiner has not set forth a prima facie case of
obviousness in the written record.
The examiner maintains that the structure of Klass will function as a wafer chuck without
the presence of the electrofluid material which changes viscosity due to the application of
the electric field because the remaining structure is a conventional chuck. (Office action at
pages 2-3 and 6.) Appellant argues that the examiner’s rejection is based upon
speculation and hindsight. (Brief at pages 10-11.) We agree with appellant. Appellant
argues that the system of Klass could not be used in a vacuum as claimed. (See brief at
page 10.) We agree with appellant. The examiner maintains that the rejection is based
“upon sound principles.” (See Office action at page 6.) The examiner maintains that Klass
discloses a conventional chuck and it will work in a vacuum to attract wafers. Furthermore,
the examiner maintains that the examiner has set forth reasons that Klass will work and it is
up to applicant to prove that such will not perform as reasonablely set forth by the
examiner. (See answer at page 6.) We disagree with the examiner. The initial burden is
upon the examiner to establish a prima facie case of obviousness. Specifically, the
examiner must establish a motivation or convincing line of reasoning why the skilled artisan
would have been motivated to modify the teachings of Klass to remove the electrofluid and
to use the apparatus in a vacuum. The examiner maintains that the structure is the same
as a conventional electrostatic chuck, yet the examiner does not set forth a convincing line
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of reasoning to remove the electrofluid in light of the discussion throughout Klass that the
fluid forms the holding force. Klass discloses that the use of three phase power is
convenient and provides improved holding power. (Klass at col. 2, lines 58-62.) Klass
further discloses that the “holding power of the device is dependent upon the number of
electrodes employed, the number of phases of the potential employed, the magnitude of
the applied potential, and the nature of the electrofluid film. Conventional electrofluids
adapted for use in alternating potential fields may be employed to secure the chuck and
object to be held together.” (Klass at col . 3, lines 40- 45.) The examiner maintains that
the operation in a vacuum is discussed in paper number 15, page 6, paragraph 7, but that
portion of the Office action neither provides any line of reasoning to remove the electofluid
nor to use the apparatus in a vacuum. Therefore, the examiner has not established a
prima facie case of obviousness with the proposed modification of Klass.
In the answer at page 3 the examiner incorporates the rejection set forth in paper
number 15. The examiner further relies on the fact that Klass is classified in
class/subclass 361/234 where electrostatic chucks may be classified. This argument is
not persuasive as a motivation for skilled artisans to modify the teachings of Klass to
remove the electrofluid absent some teaching or line of reasoning. The mere fact that this
may be done and that the structure would then be arguably the same structure as a
conventional electrostatic chuck is immaterial to the analysis and conclusion with respect
to obviousness without any additional evidence by the examiner. This is merely
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unsupported speculation on the part of the examiner that the skilled artisan would have
been motivated with the teachings of Klass alone to remove the electrofluid which Klass
discusses solely with respect to the holding force. The examiner has made no showing of
any motivation to remove the electrostatic material from the chuck. Klass discloses the
material as providing the clamping force and not the field. Klass does not disclose that the
electrofluid is an enhancing medium. The Examiner has not provided a line of reasoning
to remove the fluid. Furthermore, appellant submitted a declaration by Mr. Reuel B.
Liebert, where Mr. Liebert states that the fact that Klass employs an electrofluid would
prevent its use in a vacuum. (Declaration at page 3.) We agree with appellant.
The examiner maintains at page 5 of the answer that the declaration by
Mr. Liebert has simply provided no proof that the structure of Klass minus the electrofluid
will not function as an electrostatic chuck. Therefore, this argument is not persuasive since
we find that the examiner has not set forth a prima facie case of obviousness with respect
to Klass alone. The examiner cites various prior art references at pages 5 and 6 of the
answer in a discussion of the level of skill in the art, but the examiner has not applied/relied
upon any other teaching besides Klass in the rejection of the claims. Here, the examiner
appears to find that the relevant prior art is electrostatic chucks, as claimed, rather than
electrofluid chucks as disclosed by Klass. Here, the skilled artisan would be starting from
the teaching of Klass to modify the teachings, rather than using the electrostatic chuck as a
beginning point of the analysis. Therefore, the examiner’s argument is not persuasive.
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With respect to claim 12, the examiner maintains that the use of Klass with wafers
would have been obvious once the electrofluid was removed (Office action at page 4),
while Klass merely discloses the use with a test object which is non-magnetic, stainless-
steel rectangular test object extending coextensive with the fluid film. (See Klass at col. 4.)
Again, we find that the examiner has not set forth a prima facie case for the use of Klass
alone with wafers.
With respect to dependent claims 3,15, 5, 6, 17 and 18, the examiner has not relied
upon the teachings of Lewin and Briglia to modify the basic teachings of Klass with
respect to the removal of the electrofluid. Therefore, these combinations do not remedy
that which is lacking in Klass alone to establish a prima facie case of obviousness.
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CONCLUSION
To summarize, the decision of the examiner to reject claims 1-3, 5-15, 17-22, and 61-
66 under 35 U.S.C. § 103 is reversed.
REVERSED
JERRY SMITH )
Administrative Patent Judge )
)
)
)
) BOARD OF PATENT
JOSEPH F. RUGGIERO ) APPEALS
Administrative Patent Judge ) AND
) INTERFERENCES
)
)
)
JOSEPH L. DIXON )
Administrative Patent Judge )
JD/RWK
Appeal No. 1999-1451
Application No. 08/481,593
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GARY L. LOSER ESQ.
VICE PRESIDENT & GENERAL COUNSEL
VARIAN SEMICONDUCTOR EQUIPMENT ASSOC INC.
35 DORY ROAD
GLOUCESTER, MA 01930