Ex parte Mishio et al.

Board of Patent Appeals and Interferences

May 12, 1999

08173953 (B.P.A.I. May. 12, 1999)

Application for patent filed December 28, 1993. 1
According to the appellants, the application is a continuation
of Application No. 07/720,831, filed September 16, 1991, now
abandoned.
THIS OPINION WAS NOT WRITTEN FOR PUBLICATION
The opinion in support of the decision being entered
today (1) was not written for publication in a law
journal and (2) is not binding precedent of the
Board.
Paper No. 37
UNITED STATES PATENT AND TRADEMARK OFFICE
____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________
Ex parte KOUICHI MISHIO, SATOSHI TAKAHASHI and SHIGERU KOMATSU
____________
Appeal No. 96-3997
Application No. 08/173,9531
____________
ON BRIEF
____________
Before THOMAS, HAIRSTON and RUGGIERO, Administrative Patent
Judges.
RUGGIERO, Administrative Patent Judge.
DECISION ON APPEAL
This is a decision on appeal from the final rejection of
claims 5, 6, 8, and 9, all of the claims pending in the
present application. Claims 1-4 and 7 have been canceled.
Appeal No. 96-3997
Application No. 08/173,953
2
The claimed invention relates to a breakdown type bipolar
diode incorporated in an integrated circuit.
Claim 6 is illustrative of the invention and reads as
follows:
6. A bipolar diode comprising:
an epitaxial layer of a first conductivity type formed on
a semiconductor substrate of a second conductivity type;
an impurity region of the first conductivity type formed
in a surface portion of the epitaxial layer;
a first impurity region of the second conductivity type
formed in the surface portion of the epitaxial layer in a
manner to contact with the impurity region of the first
conductivity type;
a second impurity region of the second conductivity type
formed in contact with the impurity region of the first
conductivity type and the first impurity region; and
an insulating layer formed over the surface of the
epitaxial layer to protect a junction end of the associated
regions;
wherein said second impurity region is formed in a region
shallower than a buried layer of the first conductivity type
formed between the epitaxial layer and the semiconductor
substrate, the second impurity region having a maximal
impurity concentration at a predetermined distance from the
surface of the epitaxial layer toward an inside of the
epitaxial layer and being higher in impurity concentration
than the first impurity region,
and
wherein a breakdown of a junction of the impurity region
of the first conductivity type and the second impurity region
is caused at a location shallower than the buried layer.
Appeal No. 96-3997
Application No. 08/173,953
Copies of the translations provided by the U. S. Patent2
and Trademark Office, February 1999, of each of the Japanese
Kokai references relied on are included and relied upon for
this decision.
Since both Appellants and the Examiner have referred to3
the Japanese Kokai documents by the Kokai designation and
number rather than the inventor’s name, we will do so also in
this decision to maintain consistency.
3
The Examiner relies on the following references:
Chruma et al. (Chruma) 4,732,866 Mar. 22,
1988
Matsubara (Japanese Kokai) 56-36171 Apr. 09,2
1981
Watanabe et al. 60-229376 Nov. 14,
1985
(Japanese Kokai)
The rejections of the appealed claims are set forth by
the Examiner as follows:
1. Claims 8 and 9 stand finally rejected under 35
U.S.C.
§ 103 as being unpatentable over Japanese Kokai 60-229376
together with Japanese Kokai 56-36171.
2. Claims 5, 6, 8, and 9 stand finally rejected under
35 U.S.C. § 103 as being unpatentable over Japanese Kokai 60-
229376 together with Japanese Kokai 56-36171 and Chruma. 3
Appeal No. 96-3997
Application No. 08/173,953
The (revised) Appeal Brief was filed December 1, 1995. 4
In response to the Examiner’s Answer dated February 15, 1996,
a Reply Brief was filed April 10, 1996. The Examiner entered
the Reply Brief and submitted a supplemental Examiner’s Answer
in response dated May 30, 1996.
4
Rather than reiterate the arguments of Appellants and the
Examiner, reference is made to the Briefs and Answers for the
respective details thereof.4
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, Appellants’
arguments set forth in the Briefs along with the Examiner's
rationale in support of the rejections and arguments in
rebuttal
set forth in the Examiner's Answers. It is our view, after
consideration of the record before us, that the collective
evidence relied upon and the level of skill in the particular
art would not have suggested to one of ordinary skill in the
Appeal No. 96-3997
Application No. 08/173,953
5
art the obviousness of the invention as set forth in claims 5,
6, 8, and 9. Accordingly, we reverse.
Appeal No. 96-3997
Application No. 08/173,953
6
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, 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
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
Appeal No. 96-3997
Application No. 08/173,953
7
(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).
We note that each of the independent claims 6, 8, and 9
recites the construction of a bipolar diode in which a
subsurface breakdown region is implanted below the surface of
an epitaxial layer. The relevant portion of independent claim
6 (similar recitations of which appear in independent claims 8
and 9) recites:
wherein said second impurity region is
formed in a region shallower than a buried
layer of the first conductivity type formed
Appeal No. 96-3997
Application No. 08/173,953
8
between the epitaxial layer and the
semiconductor substrate, the second impurity
region having a maximal impurity concentration ata
predetermined distance from the surface of the
epitaxial layer toward an inside of the epitaxial
layer and being higher in impurity
concentration than the first impurity region.
The Examiner, in making the obviousness rejection (Answer,
pages 4 and 7), seeks to modify the breakdown diode of Kokai
60-229376 by substituting the buried implanted subsurface
breakdown region taught in the breakdown diode of Kokai 56-
36171 (element 5, Figure 2) for the diffused breakdown region
5 in Kokai 60-229376.
In response, Appellants assert a lack of suggestion or
motivation in the references for combining or modifying
teachings to establish a prima facie case of obviousness.
After careful review of the Kokai 60-239376 and Kokai 56-36171
references, we are in agreement with Appellants' stated
position in the Briefs. The mere fact that the prior art may
be modified in the manner 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, 23 USPQ2d 1780, 1783-84 (Fed. Cir. 1992). The
Examiner's statement of the grounds of rejection at page 4 of
Appeal No. 96-3997
Application No. 08/173,953
9
the Answer, is lacking in any rationale as to why the skilled
artisan would modify Kokai 60-239376 in such a manner. Rather
than pointing to specific information in Kokai 56-36171 that
would suggest the combination with Kokai 60-239376, the
Examiner instead has described the similarities between the
Kokai references and the claimed invention. Nowhere does the
Examiner identify any suggestion, teaching, or motivation to
combine the Kokai references nor does the Examiner establish
any findings as to the level of ordinary skill in the art, the
nature of the problem to be solved, or any other factual
findings that would support a proper obviousness analysis.
See, e.g., Pro-Mold & Tool Co. v. Great Lakes Plastics, Inc.,
75 F. 3d 1568, 37 USPQ2d 1626 (Fed. Cir. 1996). We are left
to speculate why one of ordinary skill would have found it
obvious to substitute a buried implanted subsurface breakdown
region for the diffused breakdown region in Kokai 60-239376.
The only reason we can discern is improper hindsight
reconstruction of Appellants' claimed invention. In order for
us to sustain the Examiner’s rejection under 35 U.S.C. § 103,
we would need to resort to speculation or unfounded
assumptions or rationales to supply deficiencies in the
Appeal No. 96-3997
Application No. 08/173,953
10
factual basis of the rejection before us. In re Warner, 379
F.2d 1011, 1017, 154 USPQ 173, 178 (CCPA 1967), cert. denied,
389 U.S. 1057 (1968), rehearing denied, 390 U.S. 1000 (1968).
Since we are of the view that the prior art applied by the
Examiner does not support the rejection, we do not sustain the
rejection of independent claims 6, 8, and 9.
With respect to dependent claim 5, the Examiner adds
Chruma to the combination of Kokai 60-239376 and Kokai 56-
36171 solely to meet the “silicon nitride” insulating layer
limitation. Chruma, however, does not overcome the innate
deficiencies of the combination of the Kokai references and,
therefore, we do not sustain the rejection of claim 5 under 35
U.S.C. § 103.
Appeal No. 96-3997
Application No. 08/173,953
11
In view of the foregoing, the decision of the Examiner
rejecting claims 5, 6, 8, and 9 under 35 U.S.C. § 103 is
reversed.
REVERSED
JAMES D. THOMAS )
Administrative Patent Judge )
)
)
)
) BOARD OF PATENT
KENNETH W. HAIRSTON ) APPEALS
Administrative Patent Judge ) AND
) INTERFERENCES
)
)
)
JOSEPH F. RUGGIERO )
Administrative Patent Judge )
jrg
Appeal No. 96-3997
Application No. 08/173,953
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FINNEGAN, HENDERSON, FARABOW
GARRETT & DUNNER
1300 I ST., N.W.
Washington, DC 20005-3315
JENINE GILLIS
ATTN: A copy of both Japanense
Kokai references are in the
envelope--ready to be mailed.
Appeal No. 96-3997
Serial No. 08/173,953
Judge RUGGIERO
Judge HAIRSTON
Judge THOMAS
Received: 5/4/99
Typed: 5/5/99

DECISION: REVERSED

Send Reference(s): Yes No
or Translation(s)
Panel Change: Yes No
3-Person Conf. Yes No
Remanded: Yes No
Brief or Heard
Group Art Unit: 2815
Index Sheet-2901 Rejection(s): ___________
Acts 2: ____
Palm: ____
Mailed: Updated Monthly Disk (FOIA): ____
Updated Monthly Report: ___
Appeal No. 96-3997
Application No. 08/173,953
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