Ex Parte Sriram et al

Patent Trial and Appeal Board

Jan 30, 2018

13652754 (P.T.A.B. Jan. 30, 2018)

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.
13/652,754 10/16/2012 Saptharishi Sriram 5308-1031DV 9671
65106 7590
MYERS BIGEL, P.A.
P.O. BOX 37428
RALEIGH, NC 27627
EXAMINER
YEUNG LOPEZ, FEIFEI
ART UNIT PAPER NUMBER
2899
NOTIFICATION DATE DELIVERY MODE
02/01/2018 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):
u spto @ my ersbigel. com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte SAPTHARISHI SRIRAM and QINGCHUN ZHANG
Appeal 2017-003338
Application 13/652,754
Technology Center 2800
Before MICHAEL P. COLAIANNI, JULIA HEANEY, and
JENNIFER R. GUPTA, Administrative Patent Judges.
HEANEY, Administrative Patent Judge.
DECISION ON APPEAL1
Appellant2 requests review pursuant to 35 U.S.C. § 134(a) of a
decision of the Examiner to reject claims 1 and 3-12 of Application
13/652,754. We have jurisdiction under 35 U.S.C. § 6(b). We affirm.
1 This Decision includes citations to the following documents: Specification
filed Oct. 16, 2012 (“Spec.”); Final Rejection dated Mar. 25, 2015 (“Final
Act.”); Appeal Brief filed Nov. 17, 2015 (“Br.”); corrected Claims Appendix
filed Feb. 29, 2016 (“Claims App.”); and Examiner’s Answer dated July 20,
2016 (“Ans.”).
2 Appellant is the Applicant, Cree, Inc., which is also identified as the real
party in interest. Br. 1.
Appeal 2017-003338
Application 13/652,754
BACKGROUND
The subject matter on appeal relates to a Schottky diode. Br. 2. Spec.
^ 3. Claim 1, reproduced below, is illustrative of the claimed subject matter:
1. A Schottky diode, comprising:
a drift layer on a first surface of a semiconductor
substrate;
a passivation layer on the drift layer, the passivation layer
defining a trench;
a polysilicon layer in the trench on a portion of the drift
layer exposed by the trench and on a surface of the passivation
layer; and
an anode contact on a surface of the poly-silicon layer
[an anode contact on]3, the passivation layer being free of the
anode contact,
wherein the drift layer comprises a layer including
gallium nitride (GaN) and the semiconductor substrate
comprises GaN.
Claims App. 11.
3 The bracketed claim language, “an anode contact on” that appears in the
corrected Claims Appendix filed February 29, 2016, appears to be a
typographical error. See Br. 6-7, 11 (indicating a strikethrough of bracketed
claim language).
2
Appeal 2017-003338
Application 13/652,754
THE REJECTIONS4
The Examiner maintains the following rejections of appeal:
1. Claims 1, 3, 4, and 6 are rejected under 35 U.S.C. § 103(a) as
unpatentable over the combination of Hayashi,5 Korec,6 and Cao.7
Final Act. 13-14.
2. Claim 5 is rejected under 35 U.S.C. § 103(a) as unpatentable over
the combination of Hayashi, Korec, Cao, and Shimoida.8 Final
Act. 15-16.
3. Claim 7 is rejected under 35 U.S.C. § 103(a) as unpatentable over
the combination of Hayashi, Korec, Cao, and Parikh.9 Final Act.
18.
4. Claims 8-12 are rejected under 35 U.S.C. § 103(a) as unpatentable
over the combination of Hayashi, Korec, Cao, and Shimoida. Final
Act. 19-21.
4 The Examiner withdrew the rejection of claim 5 under 35 U.S.C. § 112,
first paragraph, and the rejections of claims 1 and 3-12 as unpatentable
under 35 U.S.C. § 103(a) over combinations of references different from
those proposed in Rejections 1—4 herein. Ans. 3.
5 Hayashi, US 2007/0235745 Al, Oct. 11, 2007.
6 Korec, US 2002/0125541 Al, Sept. 12, 2002.
7 Cao, US 2007/0096239 Al, May 3, 2007.
8 Shimoida, US 2004/0031971 Al, Feb. 19, 2004.
9 Parikh, US 2003/0015708 Al, Jan. 23, 2003.
3
Appeal 2017-003338
Application 13/652,754
DISCUSSION
Appellant argues independent claims 1 and 8 as a group and do not
separately argue the dependent claims. Br. 6-7. In accordance with
37 C.F.R. § 41.37(c)(l)(iv), we select claim 1 as representative and decide
the appeal based on the representative claim alone.
The Examiner finds that Hayashi teaches a Schottky diode comprising
the components of claim 1, except that Hayashi does not teach a passivation
layer, or a drift layer and substrate comprising gallium nitride (GaN), but
rather teaches a drift layer and substrate comprising SiC. Final Act. 57-
59, 61-62, providing citations to Hayashi. The Examiner finds that Korec
teaches making an oxide layer a passivation layer, and determines that it
would have been obvious to a person of ordinary skill in the art to make
Hayashi’s oxide layer a passivation layer in order to provide the benefit of
passivating the device when forming the electrode, as taught by Korec.
Final Act. ^ 60, providing citations to Korec. The Examiner further finds
that Cao discloses the claimed GaN drift layer, and further teaches that
devices based on GaN materials, as compared to SiC, have superior high
voltage and high frequency operation. Final Act. 63, providing citations to
Cao. The Examiner thus determines it would have been obvious to a person
of ordinary skill in the art to replace the SiC material of Hayashi’s drift layer
and substrate with GaN, to obtain the benefits taught by Cao. Final Act.
64.
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Appeal 2017-003338
Application 13/652,754
Appellant does not dispute the Examiner’s findings regarding
Hayashi.10 Br. 8. Appellant argues that the rejection improperly applies
hindsight in determining that the combination of Shimoida, Korec, and Cao
discloses a Schottky diode having all of the elements of claim 1, because a
person of ordinary skill in the art would not look to Cao for a drift layer
comprising GaN. Br. 6.
Appellant’s argument is not persuasive of reversible error. Appellant
does not explain why a person of ordinary skill would not have looked to
Cao, nor does Appellant address the Examiner’s specific findings regarding
Cao, which are supported by the record. The Examiner responds to
Appellant’s argument in the Answer (Ans. 4-5), and Appellant does not
contest the Examiner’s statement (i.e., no Reply Brief has been filed).
For these reasons, we are not persuaded by Appellant’s argument for
reversal of the rejection.
SUMMARY
We affirm the rejections of claims 1 and 3-12.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a).
AFFIRMED
10 Appellant disputes the Examiner’s findings regarding Shimoida, but the
Examiner no longer relies on Shimoida in rejecting claim 1. Ans. 3
(withdrawing the rejection of claims 1, 3-6, and 8-12 under 35 U.S.C. §
103(a) over Shimoida, Korec, and Cao).
5