Ex parte Lee

Board of Patent Appeals and Interferences

Dec 14, 2000

08761883 (B.P.A.I. Dec. 14, 2000)

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for publication and is not binding precedent of the Board.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. 12
UNITED STATES PATENT AND TRADEMARK OFFICE
____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________
Ex parte CHUNG-KUANG LEE
____________
Appeal No. 1998-1102
Application No. 08/761,883
____________
ON BRIEF
____________
Before HAIRSTON, FLEMING, and RUGGIERO, Administrative Patent
Judges.
RUGGIERO, Administrative Patent Judge.
DECISION ON APPEAL
This is a decision on the appeal from the final rejection
of claims 15-22, all of the claims pending in the present
application.
The claimed invention relates to a polysilicon resistor
structure in which first and second insulating layers provide
Appeal No. 1998-1102
Application No. 08/761,883
2
a barrier to the deterioration of the polysilicon resistor.
The first insulating layer, formed of a glasseous material, is
formed directly upon the surface of a semiconductor substrate,
while the second insulating layer is formed directly upon the
first insulating layer and over the polysilicon resistor.
Appellant indicates at page 5 of the specification that the
second insulating layer is formed from a silicon oxide
material deposited using a Plasma Enhanced Chemical Vapor
Deposition (PECVD) process using silane as the silicon source
material.
Claims 15 is illustrative of the invention and reads as
follows:
15. A polysilicon resistor structure for use within
integrated circuits comprising:
a first insulating layer formed directly upon a
semiconductor substrate, the first insulating layer being
formed from a glasseous material;
a polysilicon resistor in contact with the first
insulating layer;
a second insulating layer formed upon the first
insulating layer and above the polysilicon resistor, the
second insulating layer being formed from a silicon oxide
material deposited through a Plasma Enhanced Chemical Vapor
Deposition process employing silane as the silicon source
material.
Appeal No. 1998-1102
Application No. 08/761,883
3
The Examiner relies on the following prior art:
Manning et al. (Manning) 5,232,865 Aug. 03,
1993
Cederbaum et al. (Cedarbaum) 5,381,046 Jan. 10,
1995
McArthur 5,554,884 Sep. 10, 1996
(Filed Jan. 27, 1995)
Claims 15-22 stand finally rejected under 35 U.S.C. § 103
as being unpatentable over the combination of Cederbaum and
Manning. In a separate rejection, claim 17 stands finally
rejected under 35 U.S.C. § 103 as being unpatentable over the
combination of Cederbaum, Manning, and McArthur.
Rather than reiterate the arguments of Appellant and the
Examiner, reference is made to the Brief and Answer for the
respective details.
OPINION
We have carefully considered the subject matter on
appeal, the rejections advanced by the Examiner and the
evidence of obviousness relied upon by the Examiner as support
for the rejections. We have, likewise, reviewed and taken
into consideration, in reaching our decision, Appellant’s
arguments set forth in the Brief along with the Examiner’s
Appeal No. 1998-1102
Application No. 08/761,883
4
rationale in support of the rejections and arguments in
rebuttal set forth in the Examiner’s Answer.
It is our view, after consideration of the record before
us, that the evidence relied upon and the level of skill in
the particular art would not have suggested to one of ordinary
skill in the art the obviousness of the invention as set forth
in claims 15-22. Accordingly, we reverse.
In rejecting claims under 35 U.S.C. § 103, it is
incumbent upon the Examiner to establish a factual basis to
support the legal conclusion of obviousness. See In re Fine,
837
F.2d 1071, 1073, 5 USPQ2d 1596, 1598 (Fed. Cir. 1988). In so
doing, the Examiner is expected to make the factual
determinations set forth in Graham v. John Deere Co., 383 U.S.
1,
17-18, 148 USPQ 459, 467 (1966), and to provide a reason why
one
having ordinary skill in the pertinent art would have been led
to
modify the prior art or to combine prior art references to
arrive
Appeal No. 1998-1102
Application No. 08/761,883
5
at the claimed invention. Such reason must stem from some
teaching, suggestion or implication in the prior art as a
whole
or knowledge generally available to one having ordinary skill
in
the art. Uniroyal Inc. v. Rudkin-Wiley Corp., 837 F.2d 1044,
1051, 5 USPQ2d 1434, 1438 (Fed. Cir.), cert. denied, 488 U.S.
825
(1988); Ashland Oil, Inc. v. Delta Resins & Refractories,
Inc.,
776 F.2d 281, 293, 227 USPQ 657, 664 (Fed. Cir. 1985), cert.
denied, 475 U.S. 1017 (1986); ACS Hospital Systems, Inc. v.
Montefiore Hospital, 732 F.2d 1572, 1577, 221 USPQ 929, 933
(Fed.
Cir. 1984). These showings by the Examiner are an essential
part
of complying with the burden of presenting a prima facie case
of
obviousness. Note In re Oetiker, 977 F.2d 1443, 1445, 24
USPQ2d
1443, 1444 (Fed. Cir. 1992).
Appeal No. 1998-1102
Application No. 08/761,883
6
With respect to independent claim 15, the Examiner
proposes to modify the semiconductor device structure of
Cederbaum which describes a polysilicon resistor in contact
with a glasseous material first insulating layer upon which a
second insulating layer is formed. As recognized by the
Examiner, the glasseous material insulating layer in Cederbaum
is not directly formed over the substrate, nor is it in
contact with the polysilicon resistor, as required by appealed
claim 15. To address this deficiency, the Examiner turns to
the semiconductor structure disclosed by Manning which, as
asserted by the Examiner, describes differing embodiments in
which a glass material insulator either contacts or is
isolated from the device substrate. In the Examiner’s view
(Answer, page 4):
It would have been obvious to a skilled artisan
to combine the teachings of Manning with that of
Cederbaum in [sic] especially since Manning teaches
several embodiments where the BPSG may either
directly contact or not directly contact the
substrate. This is viewed as within design
considerations of any skilled artisan.
In response, Appellants assert that the Examiner has
failed to establish a prima facie case of obviousness since no
motivation has been suggested for the Examiner’s proposed
Appeal No. 1998-1102
Application No. 08/761,883
7
combination of Cederbaum and Manning. We agree. In our view,
the Examiner’s reliance on design considerations as a basis
for the proposed combination of Cederbaum and Manning is not
well founded. Appellants’ disclosed intended function of
protecting the polysilicon resistor from deterioration due to
infiltration of mobile contaminants can only be achieved
through the particular insulator stacking arrangement recited
in appealed claim 15. In our opinion, the Examiner’s finding
of the particular claimed insulator stacking arrangement to be
merely a design consideration is totally devoid of any support
on the record.
We further note that we do not disagree with the
Examiner’s interpretation of the disclosure of Manning. This
reference, and we presume countless uncited others, provides a
teaching of insulating layers in contacting or non-contacting
relationship with a semiconductor device substrate.
Notwithstanding this prior art disclosure, however, we find no
convincing reasoning supplied by the Examiner as to how and
why the skilled artisan would apply such stacked insulator
teachings to the semiconductor device structure of Cederbaum.
The mere fact that the prior art may be modified in the manner
Appeal No. 1998-1102
Application No. 08/761,883
8
suggested by the Examiner does not make the modification
obvious unless the prior art suggested the desirability of the
modification. In re Fritch, 972 F. 2d 1260, 1266 n.14, 23
USPQ2d 1780, 1783-84 n.14 (Fed. Cir. 1992). We are left to
speculate why the skilled artisan would turn to the teachings
of Manning in which, in both described embodiments, the glass
insulating layer contacts the polysilicon resistor, in order
to modify the structure of Cederbaum which, rather than having
insulator contact with a polysilicon resistor, provides a
barrier layer therebetween. The only reason we can discern is
improper hindsight reconstruction of Appellant’s claimed
invention. Accordingly, we do not sustain the Examiner’s
obviousness rejection of claims 15-22 based on the combination
of Cederbaum and Manning.
Lastly, we have considered the McArthur reference added
by the Examiner to the combination of Cederbaum and Manning in
a separate 35 U.S.C. § 103 rejection of dependent claim 17.
It is apparent from the Examiner’s analysis (Answer, page 5),
however, that McArthur is relied upon solely to address the
specific recited boron and phosphorus weight limitations. We
find nothing, however, in the disclosure of McArthur which
Appeal No. 1998-1102
Application No. 08/761,883
9
would overcome the innate deficiencies of Cederbaum and
Manning discussed supra.
In conclusion, since the Examiner has not established a
prima facie case of obviousness, the 35 U.S.C. § 103 rejection
of independent claim 15 and claims 16-22 dependent thereon,
cannot be sustained. Therefore, the decision of the Examiner
rejecting claims 15-22 is reversed.
REVERSED

KENNETH W. HAIRSTON )
Administrative Patent Judge )
)
)
)
) BOARD OF PATENT
MICHAEL R. FLEMING ) APPEALS
Administrative Patent Judge ) AND
) INTERFERENCES
)
)
)
JOSEPH F. RUGGIERO )
Appeal No. 1998-1102
Application No. 08/761,883
10
Administrative Patent Judge )
lp
Appeal No. 1998-1102
Application No. 08/761,883
11
GEORGE 0 SAILE
20 MCINTOSH DRIVE
POUGHKEEPSIE NY 12603
Leticia
Appeal No. 1998-1102
Application No. 08/761,883
APJ RUGGIERO
APJ FLEMING
APJ HAIRSTON
DECISION: REVERSED
Send Reference(s): Yes No
or Translation (s)
Panel Change: Yes No
Index Sheet-2901 Rejection(s):
Prepared: June 9, 2001
Draft Final
3 MEM. CONF. Y N
OB/HD GAU
PALM / ACTS 2 / BOOK
DISK (FOIA) / REPORT