Ex Parte Udrea et al

Patent Trial and Appeal Board

Jan 22, 2019

15073937 (P.T.A.B. Jan. 22, 2019)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR
15/073,937 03/18/2016 Florin Udrea
57579 7590 01/24/2019
MURPHY, BILAK & HOMILLER/INFINEON TECHNOLOGIES
1255 Crescent Green
Suite 200
CARY, NC 27518
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www .uspto.gov
ATTORNEY DOCKET NO. CONFIRMATION NO.
1012-1594 / 2015P80628 1042
us
EXAMINER
CAO,PHATX
ART UNIT PAPER NUMBER
2817
NOTIFICATION DATE DELIVERY MODE
01/24/2019 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
official@mbhiplaw.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte FLORIN UDREA, GIANLUCA CAMUSO,
ALICE PEI-SHAN HSIEH, CHIU NG, YI TANG,
RAJEEV KRISHNA VYTLA, and CANHUA LI
Appeal2018-005035
Application 15/073,937
Technology Center 2800
Before JEFFREY T. SMITH, BRIAND. RANGE, and LILAN REN,
Administrative Patent Judges.
REN, Administrative Patent Judge.
DECISION ON APPEAL
Appeal2018-005035
Application 15/073,937
STATEMENT OF THE CASE
Appellants 1 appeal under 35 U.S.C. § 134(a) from a rejection of
claims 1-7, 9, 11-17, 19, 21, and 22. We have jurisdiction under 35 U.S.C.
§ 6(b ).
We affirm.
CLAIMED SUBJECT MATTER
The claims are directed to a bipolar semiconductor device having
localized enhancement regions. Claim 1, reproduced below, is illustrative of
the claimed subject matter:
1. A bipolar semiconductor device comprising a plurality of
unit cells, each of said plurality of unit cells comprising:
a drift region having a first conductivity type situated over
an anode layer having a second conductivity type opposite said
first conductivity type;
a first control trench extending through an inversion
region having said second conductivity type, and further
extending into said drift region, said first control trench adjacent
to cathode diffusions;
first and second depletion trenches, each having a
depletion electrode;
said first depletion trench being situated between said
second depletion trench and said first control trench;
an enhancement region having said first conductivity type
localized in said drift region between said first and second
depletion trenches, so that said enhancement region is not
situated adjacent said first control trench or between said first
depletion trench and said first control trench.
Claims Appendix (App. Br. 15).
1 The real parties in interest are identified as "INFINEON
TECHNOLOGIES AMERICAS CORP." Appeal BriefofNovember 17,
2017 ("App. Br."), 2. In this opinion, we also refer to the Final Action of
June 20, 2017 ("Final Act."), the Examiner's Answer of February 26, 2018
("Ans."), and the Reply Brief of April 13, 2018.
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Appeal2018-005035
Application 15/073,937
REFERENCES
The prior art relied upon by the Examiner in rejecting the claims on
appeal is:
Takahashi US 6,781,199 B2 Aug. 24, 2004
REJECTIONS
The Examiner rejects claims 1-7, 11-17, 21, and 22 under 35 U.S.C.
§ 102(a)(l) as anticipated by Takahashi. Final Act. 2.
The Examiner rejects claims 9 and 19 under 35 U.S.C. § 103(a) as
being unpatentable over Takahashi. Final Act. 5.
OPINION
Claims 1 and 11
Appellants argue that the Examiner reversibly erred in finding
Takahashi discloses "an enhancement region having said first conductivity
type localized in said drift region between said first and second depletion
trenches, so that said enhancement region is not situated adjacent said first
control trench or between said first depletion trench and said first control
trench" as recited in claim 1. App. Br. 5. More specifically, Appellants
argue that Figure 1 of Takahashi shows N layer 4 covering the entire N layer
3 and is adjacent to trench 7. Id.
The Examiner, on the other hand, finds that Takahashi describes the
recited "enhancement region" as illustrated by the region in between the
middle trenches 11 of Figure 1. Ans. 2-3. This particular region is
illustrated in Figure 1 of Takahashi, annotated by the Examiner which is
reproduced below. Further citing Figure 3 of Takahashi (annotated by the
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Appeal2018-005035
Application 15/073,937
Examiner which is reproduced below) the Examiner finds that this particular
region, confined within the middle trenches 11, is physically isolated from
the remaining parts ofN layer 4. Id. at 4. Takahashi provides that Figure 3
illustrates partial region 6a which extends perpendicularly to the direction of
the formation of trench 7. Takahashi 14:1-3. Partial region 6a "is
completely covered with an interlayer insulating film 19." Id. at 14:6-7.
The N "enhflnc;em~nt HJcglon" (4)
complete:~· confaied "betwoon
first and second dep!eHon
trenches" ( 11 J ;,ind cpmple!eiy
f9plak!q from the oirmr N
re.gions (4).
Figures 1 and 3 of Takahashi (annotated by the Examiner Ans. 3).
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Application 15/073,937
Appellants respond that the Examiner reversibly erred by finding that
the region circled (hereinafter the "circled region") in the above annotated
figures does not disclose the apparatus recited because the circled region is
outside of the first trench 7 in Takahashi. App. Br. 9; Reply Br. 2-3.
Appellants, however, do not adequately explain why this argument supports
patentability as claim 1 does not exclude the first control trench from being
outside of the enhancement region. We further note that Figure 1 of
Appellants' own specification illustrates first control trench 120 to be
outside of enhancement region 140. Spec., Fig. 1. 2
Lastly, Appellants' argument that Takahashi teaches away from claim
1 (App. Br. 11-12) is irrelevant to the anticipation rejection. "A reference is
no less anticipatory if, after disclosing the invention, the reference then
disparages it. Thus, the question whether a reference 'teaches away' from
the invention is inapplicable to an anticipation analysis." Celeritas Techs.
Ltd. v. Rockwell Int'! Corp., 150 F.3d 1354, 1361 (Fed. Cir. 1998) (citation
omitted). We accordingly sustain the anticipation rejection of claim 1 as
well as claim 11 as Appellants do not present separate arguments. See App.
Br. 12.
With regard to the remaining claims, namely, claims 2-7, 12-17, 21,
and 22, Appellants do not present arguments separate from those for claims
1 and 11 (see App. Br. 12, 14), and the anticipation rejection of claims 2-7,
12-17, 21, and 22 is sustained.
Dependent Claims 9 and 19
The dispositive issue on appeal for the obviousness rejection of
dependent claims 9 and 19 is whether the combined prior art teaches or
2 Application No. 15/073,937 or "Spec."
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Application 15/073,937
suggests "a third depletion trench adjacent to said first and second depletion
trenches, wherein said second depletion trench is situated between said third
depletion trench and said first depletion trench, wherein said enhancement
region is localized in said drift region between said first, second, and third
depletion trenches." App. Br. 13 ( emphasis omitted).
Appellants argue that the Examiner reversibly erred in combining the
embodiments in Figures 1 and 32 of Takahashi because the embodiment in
Figure 32 lacks a hole trapping layer illustrated in Figure 1. App. Br. 13-14.
Appellants argue that the presence or absence of such a hole trapping layer
would negatively impact the operability of the apparatus. Id. at 14.
"[W]hen a patent claims a structure already known in the prior art that
is altered by the mere substitution of one element for another known in the
field, the combination must do more than yield a predictable result." KSR
Int'! Co. v. Teleflex Inc., 550 U.S. 398,416 (2007) (citing United States v.
Adams, 383 U.S. 39, 50-51 (1966)).
In this case, the open-ended apparatus claims neither recite nor
preclude a hole trapping layer and Appellants have not directed us to
evidence in showing that the Examiner reversibly erred in finding that a
skilled artisan would have combined the known prior art components to
arrive at the recited structure. See Invitrogen Corp. v. Biocrest Mfg., L.P.,
327 F.3d 1364, 1368 (Fed. Cir. 2003) ("The transition 'comprising' in a
method claim indicates that the claim is open-ended and allows for
additional steps."). "Combining the teachings of references does not involve
an ability to combine their specific structures." In re Nievelt, 482 F.2d 965,
968 (CCP A 1973) ( emphasis omitted). As to any purported negative impact
on operability, Appellants have not directed us to evidence supporting the
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Application 15/073,937
argument and such "[a]ttomeys' argument is no substitute for evidence."
Johnston v. IVAC Corp., 885 F.2d 1574, 1581 (Fed. Cir. 1989).
Furthermore, Appellants do not argue that the Examiner's proposed
apparatus would be inoperable - only that it would be less than optimal,
according to Appellants. App. Br. 14. It is, of course, well-established that
a finding of obviousness does not require superior or equal performance
compared with the prior art. See In re Mouttet, 686 F.3d 1322, 1334 (Fed.
Cir. 2012) ("[J]ust because better alternatives exist in the prior art does not
mean that an inferior combination is inapt for obviousness purposes."). We
sustain the obviousness rejection of dependent claims 9 and 19.
DECISION
The Examiner's decision 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). See 37 C.F.R.
§ 1.136(a)(l )(iv).
AFFIRMED
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