Ex Parte Hagleitner et al

Patent Trial and Appeal Board

Dec 6, 2016

13414286 (P.T.A.B. Dec. 6, 2016)

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.
13/414,286 03/07/2012 Helmut Hagleitner 5308-1500 4993
65106 7590
MYERS BIGEL, P.A.
P.O. BOX 37428
RALEIGH, NC 27627
12/08/2016 EXAMINER
NARAGHI, ALI
ART UNIT PAPER NUMBER
2896
NOTIFICATION DATE DELIVERY MODE
12/08/2016 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):
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 HELMUT HAGLEITNER and
SAPTHARISHI SRIRAM
Appeal 2015-005960
Application 13/414,286
Technology Center 2800
Before BRADLEY R. GARRIS, WESLEY B. DERRICK, and
DEBRA L. DENNETT, Administrative Patent Judges.
DENNETT, Administrative Patent Judge.
DECISION ON APPEAL1
STATEMENT OF THE CASE
Appellants2 appeal under 35U.S.C. § 134 from a rejection of claims
1, 4, and 10-14. We have jurisdiction under 35 U.S.C. § 6(b).
We AFFIRM.
1 In our Opinion below, we refer to the Final Action mailed March 11, 2014
(“Final Act.”), the Appeal Brief filed August 13, 2014 (“App. Br.”), the
Examiner’s Answer mailed March 26, 2015 (“Ans.”), and the Reply Brief
filed May 26, 2015 (“Reply Br.”).
2 Appellants identify Cree, Inc. as the real party in interest (App. Br. 1).
Appeal 2015-005960
Application 13/414,286
The claims are directed to semiconductor devices comprising a
Schottky contact. Claim 1, reproduced below with the disputed term
highlighted, is illustrative of the claimed subject matter:
1. A semiconductor device comprising:
a semiconductor body;
a Schottky contact comprising:
a Schottky layer comprising a first metal and
formed on the semiconductor body;
a first diffusion barrier layer formed from a
portion of the Schottky layer and comprising a silicide of the
first metal and formed on at least a portion of the Schottky
layer, and
a third layer comprising a second metal and
formed on the first diffusion barrier layer.
App. Br. 9 (Claims App’x).
REFERENCES
The prior art relied upon by the Examiner in rejecting the claims on
appeal is:
Ando et al. (“Ando”) US 2005/0151255 A1 July 14, 2005
Nanjoetal. US 8,035,130 B2 Oct. 11,2011
(“Nanjo”)
REJECTIONS
Claims 1, 4, and 10-14 stand rejected under 35 U.S.C § 103(a) as
being unpatentable over Nanjo in view of Ando.3 Final Act. 2.
3 Claims 2, 3, and 5—9 are objected to as being dependent upon a rejected
base claim (claim 1). Final Act. 4. The Examiner finds the claims to be
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Appeal 2015-005960
Application 13/414,286
OPINION
Claim 1 is the sole independent claim on appeal. Appellants argue the
claims as a group, thus the dependent claims stand or fall with claim 1.
We sustain the 103(a) rejection for the reasons given in the prior
Office Action and the Answer. We add the following:
The Examiner finds that Nanjo discloses a gate structure formed on a
semiconductor layer having all the elements disclosed in Appellants’
Specification, but does not
explicitly disclose a Schottky layer comprising a first metal and
formed on the semiconductor body; a first diffusion barrier
layer formed form a portion of the [Sjchottky layer and
comprising a silicide of the first metal and formed on at least a
portion of the Schottky layer; and a third layer comprising a
second metal and formed on the first diffusion barrier layer.
Final Act. 2. The Examiner finds that Ando discloses the above elements
missing from Nanjo. Id. at 3. The Examiner contends that one of ordinary
skill in the art at the time of the invention would have found it obvious to
modify Nanjo with the teachings of Ando so a gate structure as in Ando is
formed in order to have a heat resistant Schottky junction gate layer. Id.
Appellants limit their argument to the limitation “a first diffusion
barrier layer formed from a portion of the Schottky layer and comprising a
silicide of the first metal and formed on at least a portion of the Schottky
layer.” App. Br. 4—5. The Examiner contends that the limitation describes a
product-by-process. Final Act. 5; Ans. 3.
allowable if rewritten in independent form including all of the limitations of
the base claim and any intervening claims. Id.
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Appeal 2015-005960
Application 13/414,286
Appellants dispute that “a first diffusion barrier layer formed from a
portion of the Schottky layer and comprising a silicide of the first metal and
formed on at least a portion of the Schottky layer” is product-by-process
language. App. Br. 5. Appellants direct us to Figures 2 and 3 of the
application, reproduced below, as support for this position.
Figure 2 of the application illustrates a Schottky gate contact
precursor according to one embodiment of the disclosure. Spec. 113.
Figure 3 of the application illustrates a Schottky gate contact after the
Schottky gate contact precursor is subjected to thermal annealing according
to one embodiment of the disclosure. Id. 114.
According to Appellants, in Figure 2, a Schottky layer 34P that
includes nickel is initially formed while a first diffusion barrier layer 36P,
which includes silicon, is formed over the Schottky layer 34P. App. Br. 6.
During an annealing process, a portion of the nickel in the Schottky layer
34P diffuses into the first diffusion barrier layer 36P, resulting in the first
diffusion barrier layer 36 including a portion of the Schottky layer 34, such
that the first diffusion barrier layer 36 is formed from a portion of the
Schottky layer 34. Id. Appellants contend that the structure shown in Figure
3 of the application is a Schottky gate contact 30 that forms a portion of a
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Appeal 2015-005960
Application 13/414,286
semiconductor device claimed. Id. Appellants argue that the device
illustrated in “Figure 3 is an end product where the first diffusion barrier
layer 36 is formed from a portion of the Schottky layer 34, as shown by the
notation NixSi, where the Ni diffused from the Schottky layer 34.” Id.
The Examiner notes that claim 1 states three requirements for the first
diffusion barrier: (1) it is “formed from a portion of the Schottky layer”; (2)
it comprises “a silicide of the first metal”; and (3) it is “formed on at least a
portion of the Schottky layer.” Ans. 3 (emphasis in original).
With regard to the first requirement, the Examiner contends that the
phrase “formed from” is directed toward the process of making the Schottky
layer, thus a product-by-process limitation. Id. The Examiner argues that
Appellants have the burden of showing that the method language necessarily
produces a structural difference. Id. at 3^4 (citing MPEP § 2113).
According to the Examiner, without such showing, the language “first
diffusion barrier layer formed from a portion of the Schottky layer” only
requires that the first diffusion barrier layer comprises at least one
component which is also included within the Schottky layer. Id. at 4. The
Examiner finds that Ando teaches a Schottky layer comprising a first metal
(platinum) and a first diffusion barrier layer which also comprises the first
metal of platinum. Id.
With regard to the second requirement, the Examiner finds that Ando
teaches a first diffusion barrier is a platinum silicide, which is a silicide of
the first metal layer (platinum). Id.
With regard to the third requirement, the Examiner finds that Ando
teaches a first diffusion barrier layer is formed on the Schottky layer. Id.
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Appeal 2015-005960
Application 13/414,286
The Examiner relies on the structure in Ando as teaching a Schottky
layer comprising a first metal (platinum), a first diffusion barrier layer which
comprises the silicide of the first metal (platinum silicide) which is formed
on the Schottky layer. Id. The Examiner further argues that the “formed
from” language of claim 1 is a product-by-process limitation which merely
requires that the first diffusion barrier comprise the first metal. Id. at 5.
Appellants cite to MPEP § 2113 in stating the “structure implied by
the process steps should be considered when assessing the patentability of
product-by-process claims over the prior art, especially where the product
can only be defined by the process steps by which the product is made.”
App. Br. 6—7. The structure implied by the process step here is a first
diffusion barrier layer comprising a silicide of the first metal. The claim
language does not imply that the process described in claim 1 results in a
structure that differs from the prior art to which the Examiner directs us.
Appellants provide no evidence that the platinum-silicide barrier layer taught
by Ando differs from the first diffusion barrier layer of claim 1 wherein
platinum is the first metal.
Appellants’ arguments lack persuasive merit. The fundamental
rationale of the rejection presented in the Office Action and Answer is that
the “formed from” language of claim 1 invokes a product-by-process
limitation. The patentability of a patent with a product-by-process limitation
depends on the product itself, and not on the method of production. See In
re Thorpe, 111 F.2d 695, 697 (Fed. Cir. 1985) (“If the product in a product-
by-process claim is the same as or obvious from a product of the prior art,
the claim is unpatentable even though the prior product was made by a
different process.”); see also SmithKline Beecham Corp. v. Apotex Corp.,
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Appeal 2015-005960
Application 13/414,286
439 F.3d 1312, 1315 (Fed. Cir. 2006) (“[0]nce a product is fully disclosed in
the art, future claims to that same product are precluded, even if that product
is claimed as made by a new process.”). Where, as here, the Examiner
provides a rationale tending to show that the claimed product appears to he
the same or similar to that of the prior art, although produced by a different
process, the burden shifts to Appellants to come forward with evidence
establishing an unobvious difference between the claimed product and the
prior art product. In re Marosi, 710 F.2d 799, 802 (Fed. Cir. 1983).
For the reasons stated above and given by the Examiner, we sustain
the § 103(a) rejection of the appealed claims as unpatentable over Nanjo in
view of Ando.
DECISION
For the above reasons, the Examiner’s rejection of claims 1, 4, and
10—14 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)(l)(iv).
AFFIRMED
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