Ex Parte Harada et al

Patent Trial and Appeal Board

Nov 8, 2017

13634860 (P.T.A.B. Nov. 8, 2017)

United States Patent and Trademark Office
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
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
13/634,860 09/13/2012 Shin Harada 92396-336744 2651
26694 7590
VENABLE LLP
P.O. BOX 34385
WASHINGTON, DC 20043-9998
EXAMINER
WILSON, SCOTT R
ART UNIT PAPER NUMBER
2826
NOTIFICATION DATE DELIVERY MODE
11/13/2017 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):
PTOMail@Venable.com
cavanhouten@venable.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL
AND APPEAL BOARD
Ex parte SHIN HARADA, MAKOTO SASAKI, TARO NISHIGUCHI,
KYOKO OKITA, KEIJI WADA, and TOMIHITO MIYAZAKI
Appeal 2016-007260
Application 13/634,860
Technology Center 2800
Before BRADLEY R. GARRIS, KAREN M. HASTINGS, and
RAE LYNN P. GUEST, Administrative Patent Judges.
HASTINGS, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Appellants seek our review under 35 U.S.C. § 134 of the Examiner’s
decision rejecting claims 1 and 3—12 under 35 U.S.C. § 103(a) as
unpatentable over at least the basic combination of Kudou (US
2010/0075474 Al; publ. Mar. 25, 2010) in view of Feng (Gan Feng et al.,
Characterization of stacking faults in 4H-SiC epilayers by room-
temperature microphotoluminescence mapping, 92 Appl. Phys. Lett.,
Appeal 2016-007260
Application 13/634,860
221906-1—221906-3 (2008)).1 We have jurisdiction over the appeal under
35 U.S.C. § 6(b).
For the reasons presented by Appellants in the briefs, we REVERSE.
Claims 1 is illustrative of the claimed subject matter:
1. A semiconductor device having a current path,
comprising:
a semiconductor layer constituting at least a part of said
current path and made of silicon carbide; and
a substrate that has a first surface supporting said
semiconductor layer and a second surface opposite to said first
surface, that is made of silicon carbide having a 4H type single­
crystal structure, and that has a physical property in which a
ratio of a peak strength in a wavelength of around 500 nm to a
peak strength in a wavelength of around 390 nm is 0.1 or
smaller in photoluminescence measurement,
wherein said substrate has said physical property at said
second surface.
ANALYSIS
The Examiner has the initial burden of establishing a prima facie case
of obviousness based on an inherent or explicit disclosure of the claimed
subject matter under 35 U.S.C. § 103. In re Oetiker, 977 F.2d 1443, 1445
(Fed. Cir. 1992) (“[T]he examiner bears the initial burden, on review of the
prior art or on any other ground, of presenting a prima facie case of
unpatentability”). After review of the respective positions provided by
Appellants and the Examiner, we agree with Appellants that the Examiner
has not met the applicable burden in this case.
1 While the Examiner relies upon various additional prior art references with
Kudou and Feng to reject various dependent claims (see, e.g., Final Action
7, 8), Appellants’ arguments are solely directed to claim 1 (Appeal Br.,
Reply Br. generally).
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Appeal 2016-007260
Application 13/634,860
In the § 103 rejections of all the claims, the Examiner relies upon
Kudou to exemplify a substrate made of 4H-SiC and Feng’s teaching or
inference that, since obtaining the recited property is desirable for an
epitaxial layer of 4H-SiC grown on a substrate, it would have been a
desirable property to have for a 4H-SiC substrate as well (e.g., Final Action
5,6; Ans. generally).
Feng is concerned with measuring undesirable stacking faults in 4H-
SiC epilayers (Feng, abstract). As Appellants point out, Feng is not
concerned with this property for a substrate formed of 4H-SiC (e.g., Appeal
Br. 9, 10, quoting Feng p 221906, p. 1 right column which states “Due to the
considerable difference of the carrier lifetime between the epilayer and the
substrate,... the information inside the substrate can hardly be observed in
the PF spectra”, and stating the variation of PF intensity can be used “only
in the epilayers”). A preponderance of the evidence supports Appellants’
position that this disclosure is insufficient to establish obviousness of the
claimed property for the second side of the substrate as recited in
independent claim 1 (App Br. 9, 10; Reply Br. 9, 10). Appellants point out
that substrates and epitaxial layers have substantially different properties due
to different dopant concentrations and impurity levels (Reply Br. 9, 10).
Indeed, Feng does discuss “formation mechanisms” of SFs (Feng Abstract)
and states “they are often reported in heavily nitrogen-doped 4H-SiC
annealed at high temperatures or subjected to external mechanical loading”
(Feng, p. 221906, left hand column, first full sentence).
The Examiner does not direct us to, or rely upon any disclosure in
Feng or Kudou about how to avoid or eliminate stacking faults in a substrate
layer of 4H-SiC (or in an epitaxial layer) (Ans. generally). Specifically, the
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Appeal 2016-007260
Application 13/634,860
Examiner has not adequately addressed Appellants’ arguments that
Appellants discovered a problem with 4H-SiC substrates and solved it by
removing damage layers in order to achieve the claimed property at the
second surface of the substrate, and the applied prior art does not teach how
to arrive at such a property at the required second surface of the substrate
(see, e.g., Appeal Br. 13; Reply Br. 10, 11; Spec. 5:11—15; Spec. 6:2—5;
Spec. 13:1—22; Ans. generally). A preponderance of the evidence supports
Appellants’ position that since the applied prior art does not recognize the
problem,2 there is no evidence one of ordinary skill would have known how
to ensure that the substrate of Kudou would have had the claimed property at
the second surface as recited in independent claim 1. It is well settled that
when a claimed product reasonably appears to be substantially the same as a
product disclosed by the prior art, the burden is on the applicant to prove that
the prior art product does not necessarily or inherently possess
characteristics attributed to the claimed product, and that it is of no moment
whether the rejection is based on § 102 or § 103 since the burden is on the
applicant is the same. In re Spada, 911 F.2d 705, 708 (Fed Cir. 1990); In re
Best, 562 F.2d 1252, 1255 (CCPA 1977). Here, however, the Examiner has
2 It is noted that the translated office action of the Japanese Patent office
submitted August 2016 (after the Examiner’s Answer and the filing of the
Reply Brief) does rely upon prior art that teaches eliminating damage layers
of a substrate, however, the Examiner has not pointed us to any such
evidence in this appeal. The Board relies on the involved parties to focus on
the issues and decides on those issues based on facts and arguments
presented by the involved parties. See Ex parte Frye, 94 USQP2d 1072,
1075 (BPAI 2010) (precedential). While the Board is authorized to enter a
new ground of rejection, this authority is discretionary. See 37 C.F.R.
§ 41.77(b). We decline to make a new ground and leave it to the Examiner
to consider this new evidence of record in the first instance.
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Appeal 2016-007260
Application 13/634,860
not directed us to any evidence that the product/substrate disclosed in the
prior art is substantially the same and/or is produced by substantially the
same method described in Appellants’ Specification so as to shift the burden
to Appellants to prove otherwise. While the Examiner states “the method of
achieving the physical property ... is to have a SF density of zero, as taught
in the PL method of Feng” (Ans. 15), the method of Feng is merely a
measurement of the micro-PL spectrum in epitaxial layers to map stacking
faults or lack thereof (Feng Abstract); Feng does not address the presence of
SFs in substrates nor teach how to avoid SFs in a 4H-SiC substrate.
A preponderance of the evidence supports the Appellants’ position
that the Examiner has not met the initial burden of establishing a prima facie
case of obviousness of the claimed subject matter under 35 U.S.C. § 103(a),
respectively. Oetiker, 977 F.2d at 1445 (“[T]he examiner bears the initial
burden, on review of the prior art or on any other ground, of presenting a
prima facie case of unpatentability”).
The Examiner’s rejections and response to argument presented in the
Answer do not persuasively address the contentions raised by the Appellants
in their briefs (Ans. generally).
Under these circumstances, we are constrained to reverse all of the
§ 103(a) rejections before us.
REVERSED
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