Ex Parte LO et al

Board of Patent Appeals and Interferences

Apr 29, 2002

08295593 (B.P.A.I. Apr. 29, 2002)

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written for publication and is not binding precedent of the Board.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. 24

UNITED STATES PATENT AND TRADEMARK OFFICE
_____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
_____________
Ex parte CHI-FUNG LO and JOHN TURN
_____________
Appeal No. 1998-0242
Application 08/295,593
______________
ON BRIEF
_______________
Before KIMLIN, WALTZ and DELMENDO, Administrative Patent Judges.
KIMLIN, Administrative Patent Judge.
DECISION ON APPEAL
This is an appeal from the final rejection of claims 1,
4-11, 13, 14 and 16-19. Claim 1 is illustrative:
1. Apparatus for making metal oxide sputtering
targets, comprising:
a graphite die assembly, including a graphite ring
and a pair of opposing graphite punches, defining a die
Appeal No. 1998-0242
Application No. 08/295,593
made of a material selected from the group consisting
of Al O , MgO, ZrO , SiC and Si N , and being capable of2 3 2 3 4
withstanding hot-pressing at a temperature of at least
1100ºC;
whereby said barrier sleeve substantially prevents
a reducing gas from penetrating to the powdered metal
oxide target starting material, said barrier sleeve
being substantially unreactive with the powdered target
starting material during hot pressing, and said
powdered target starting material being volatile and
thermally unstable during hot pressing.
The examiner relies upon the following references as
evidence of obviousness:
Brierley 2,886,849 May 19, 1959
Weigert DE 41 24 471 C1 Jun. 24, 19911
Appellants’ claimed invention is directed to an apparatus
and process for making metal oxide sputtering targets. The
apparatus comprises a graphite die assembly and a barrier sleeve
which lines the graphite die assembly die cavity. The barrier
sleeve is made of a material selected from a Markush group that
includes Al O . According to appellants, “[t]he purpose of the2 3
barrier sleeve is to substantially prevent a reducing gas from
penetrating to the powdered metal oxide starting material” (page
Appeal No. 1998-0242
Application No. 08/295,593
Appealed claims 1, 4-7, 11, 13, 14, 16, 18 and 19 stand
rejected under 35 U.S.C. § 103 as being unpatentable over
Weigert. Claims 8-10 and 17 stand rejected under 35 U.S.C. § 103
as being unpatentable over Weigert in view of Brierley.
We have thoroughly reviewed the respective positions
advanced by appellants and the examiner. In so doing, we find
ourselves in agreement with appellants that the prior art cited
by the examiner fails to establish a prima facie case of
obviousness for the claimed subject matter. Accordingly, we will
not sustain the examiner’s rejections.
The examiner cites Example 1 of Weigert for disclosing an
apparatus and method for forming metal oxide sputtering targets
wherein a graphite is employed which is lined with boron nitride
rather than appellants’ Al O . However, the examiner also cites2 3
Example 2 of Weigert for disclosing pressing powdered metal oxide
in a pressing can which is lined with Al O paper. Since2 3
reference Example 2 demonstrates that Al O does not react with2 3
indium oxide and tin oxide, the examiner concludes that it would
Appeal No. 1998-0242
Application No. 08/295,593
While we appreciate that there is a certain appeal to the
examiner’s approach in formulating the rejection, it is our
judgment that the examiner’s rejection is based upon the
impermissible use of hindsight. It is Example 1 of Weigert which
utilizes appellants’ graphite die assembly and this Example only
discloses the use of boron nitride as a lining for the graphite
mold. Example 2 of Weigert, which discloses the use of Al O2 3
paper, does so in the context of a steel pressing can, not a
graphite mold. There is no evidence of record that materials
which are typically used as linings for steel pressing cans are
interchangeable with linings for graphite hot pressing molds.
Consequently, there is no factual support for the examiner’s
conclusion that it would have been obvious to substitute a lining
material used in a steel pressing can for a lining of a hot
pressing mold. The examiner does not propose that the Al O2 3
paper of Weigert’s Example 2 be substituted for the boron nitride
lining of Weigert’s Example 1. In our view, the examiner’s
rationale regarding the inertness of Al O to the metal oxide2 3
Appeal No. 1998-0242
Application No. 08/295,593
Brierley, cited by the examiner for additional features
recited in claims 8-10 and 17, does not remedy the deficiency of
Weigert discussed above.
In conclusion, based on the foregoing, we are constrained to
reverse the examiner’s rejections.
REVERSED
EDWARD C. KIMLIN )
Administrative Patent Judge )
)
)
) BOARD OF PATENT
THOMAS A. WALTZ ) APPEALS AND
Administrative Patent Judge ) INTERFERENCES
)
)
)
ROMULO H. DELMENDO )
Administrative Patent Judge )
vsh
Appeal No. 1998-0242
Application No. 08/295,593
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