Ex Parte O et al

Patent Trial and Appeal Board

Oct 28, 2016

13610993 (P.T.A.B. Oct. 28, 2016)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
13/610,993 09/12/2012
27820 7590 11/01/2016
WITHROW & TERRANOVA, PLLC
106 Pinedale Springs Way
Cary, NC 27511
FIRST NAMED INVENTOR
Michael John O'Loughlin
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.
1194-114 2159
EXAMINER
ALAM, MOHAMMED R
ART UNIT PAPER NUMBER
2828
NOTIFICATION DATE DELIVERY MODE
11/01/2016 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):
patents@wt-ip.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte MICHAEL JOHN O'LOUGHLIN, LIN CHENG,
ALBERT AUGUSTUS BURK, JR., and ANANT KUMAR AGARWAL 1
Appeal2015-005987
Application 13/610,993
Technology Center 2800
Before BRADLEY R. GARRIS, JAMES C. HOUSEL, and
DEBRA L. DENNETT, Administrative Patent Judges.
GARRIS, Administrative Patent Judge.
DECISION ON APPEAL
Pursuant to 35 U.S.C. § 134, Appellants appeal from the Examiner's
rejections under 35 U.S.C. § 103(a) of independent claims 1and20 as
unpatentable over Tsuchida et al. (US 2009/0039358 Al, published Feb. 12,
2009) ("Tsuchida") and dependent claims 2-10, 13-19, and 23-35 as
unpatentable over this reference alone or in combination with an additional
prior art reference. We have jurisdiction under 35 U.S.C. § 6.
1 Cree, Inc. is identified as the real party in interest. App. Br. 1.
Appeal2015-005987
Application 13/610,993
We AFFIRM.
Appellants claim a method and a semiconductor die wherein a carbon
vacancy reduction material is ion implanted into a silicon carbide epitaxial
structure followed by annealing to diffuse carbon atoms substantially
throughout the epitaxial structure "such that an average carrier lifetime in the
silicon carbide epitaxial structure is at least three times an average carrier
lifetime in the silicon carbide epitaxial structure before ion implanting the
carbon vacancy reduction material" (independent claims 1 and 20).
A copy of representative claims 1 and 20, taken from the Claims
Appendix of the Appeal Brief, appears below.
1. A method comprising:
providing a substrate;
forming a silicon carbide epitaxial structure on the substrate;
ion implanting a carbon vacancy reduction material into a surface of
the silicon carbide epitaxial structure; and
annealing the silicon carbide epitaxial structure to mobilize the carbon
vacancy reduction material to diffuse carbon atoms substantially throughout
the silicon carbide epitaxial structure, such that an average carrier lifetime in
the silicon carbide epitaxial structure is at least three times an average carrier
lifetime in the silicon carbide epitaxial structure before ion implanting the
carbon vacancy reduction material.
20. A semiconductor die comprising:
a substrate; and
a silicon carbide epitaxial structure on the substrate and comprising
carbon vacancy reduction material, which has been implanted into a surface
of the silicon carbide epitaxial structure, wherein the silicon carbide epitaxial
structure has been annealed to mobilize the carbon vacancy reduction
material to diffuse carbon atoms substantially throughout the silicon carbide
epitaxial structure, such that an average carrier lifetime in the silicon carbide
epitaxial structure is at least three times an average carrier lifetime in the
silicon carbide epitaxial structure before ion implanting the carbon vacancy
reduction material.
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Appeal2015-005987
Application 13/610,993
Appellants do not present separate arguments specifically directed to
the dependent claims under rejection (App. Br. 5-8). Therefore, the
dependent claims will stand or fall with their parent independent claims 1
and 20.
We sustain the rejections before us for the reasons expressed in the
Final Action, the Answer, and below.
The Examiner finds that Tsuchida discloses ion implanting a carbon
vacancy reduction material into a silicon carbide epitaxial layer followed by
annealing in order to improve carrier lifetime of the silicon carbide layer
(Final Action 4--5 (citing, e.g., i-f 33)). Appellants do not dispute this finding
(see generally App. Br.). Instead, Appellants argue that "Tsuchida does not
disclose or suggest annealing a silicon carbide epitaxial structure such that
an average carrier lifetime is at least three times an average carrier lifetime
in the silicon carbide epitaxial structure before ion implanting a carbon
vacancy reduction material" (App. Br. 5). In this regard, Appellants
emphasize that Tsuchida discloses "an average carrier lifetime doubles" (id.
at 7 (citing at n. 17 Tsuchida Fig. 18)) and that "embodiments of the present
invention, which triples an average carrier lifetime, achieves the carrier
lifetime using parameters [e.g., annealing temperature] disclosed in Tsuchida
where a carrier lifetime disclosed in Tsuchida only doubles" (id.).
In response, the Examiner points out that the general trend for
improving average carrier lifetime is known in Tsuchida (Ans. 2-3) and that
under the same or similar conditions (e.g., annealing temperature)
Tsuchida's silicon carbide epitaxial structure "must behave in the same way
as the applicant's as far as the average carrier lifetime is concem[ed]" (id. at
3).
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Appeal2015-005987
Application 13/610,993
As explained inin re Best, 562 F.2d 1252, 1255 (CCPA 1977):
Where, as here, the claimed and prior art products are identical
or substantially identical, or are produced by identical or
substantially identical processes, the PTO can require an
applicant to prove that the prior art products do not necessarily
or inherently possess the characteristics of his claimed product.
Whether the rejection is based on "inherency" under 35 U.S.C.
102, on "prima facie obviousness" under 35 U.S.C. 103, jointly
or alternatively, the burden of proof is the same, and its fairness
is evidenced by the PTO' s inability to manufacture products or
to obtain and compare prior art products.
(Internal citations and footnote omitted.)
The record reflects that Tsuchida teaches or would have suggested the
identical or substantially identical materials and process parameters used to
obtain the claimed average carrier lifetime, and Appellants do not argue
otherwise (see generally App. Br.). These circumstances support the
Examiner's above determination that Tsuchida's silicon carbide epitaxial
structure must behave in the same way as Appellants' identical structure,
when each is subjected to the same processing conditions. When so
processed, the epitaxial structure of Tsuchida necessarily and inherently
would possess the same average carrier lifetime improvement as the claimed
structure.
Appellants argue that the Examiner "is relying on possibilities, or, at
best probabilities, in order to maintain the rejection" (Reply Br. 4).
We do not agree. It is well-settled that the prior art need only meet
the inherently disclosed limitation to the extent the claimed invention does.
King Pharms., Inc., v. Eon Labs, Inc., 616 F.3d 1267, 1276 (Fed. Cir. 2010).
For the reasons previously explained, the epitaxial structure of Tsuchida
necessarily or inherently would possess the claimed average carrier lifetime
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Appeal2015-005987
Application 13/610,993
to the same extent as the claimed epitaxial structure (i.e., to the extent these
same structures are processed in the same way).
In summary, Appellants fail to reveal error in the § 103 rejection of
independent claims 1 and 20 as unpatentable over Tsuchida.
The decision of the Examiner 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).
AFFIRMED
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