Ex Parte Moroz et al

Patent Trial and Appeal Board

Mar 28, 2016

11928142 (P.T.A.B. Mar. 28, 2016)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR
111928,142 10/30/2007 Victor Moroz
36454 7590 03/30/2016
SYNOPSYS, INC C/O HA YNES BEFFEL & WOLFELD LLP
P.O. BOX366
HALF MOON BAY, CA 94019
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.
SYNP 0898-1 6946
EXAMINER
WHALEN, DANIEL B
ART UNIT PAPER NUMBER
2829
NOTIFICATION DATE DELIVERY MODE
03/30/2016 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):
docket@hmbay.com
pair_hbw@firsttofile.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte VICTOR MOROZ and DIPANKAR PRAMANIK
Appeal2014-004110
Application 11/928,142
Technology Center 2800
Before BRADLEY R. GARRIS, ROMULO H. DELMENDO, and
CHRISTOPHER L. OGDEN, Administrative Patent Judges.
DELMENDO, Administrative Patent Judge.
DECISION ON APPEAL
The Appellants 1 seek our review under 35 U.S.C. § 134(a) of a final
decision of the Primary Examiner to reject claims 21-23 and 25-29 under 35
U.S.C. § 102(b) as anticipated by Yu et al. (US 6,689,671 Bl issued
February 10, 2004; hereinafter "Yu").2 We have jurisdiction under 35
U.S.C. § 6(b).
1 The Appellants state that the Real Party in Interest is "Synopsys, Inc."
(Appeal Brief filed September 17, 2013, hereinafter "Appeal Br.," 3).
2 See App. Br. 3, 5-19; Examiner's Answer entered November 21, 2013,
hereinafter "Ans.," 2-9; Final Office Action entered February 4, 2013,
hereinafter "Final Act.," 3-5.
Appeal2014-004110
Application 11/928,142
We reverse.
BACKGROUND
The subject matter on appeal relates to a method for fabricating a
semiconductor (Specification, hereinafter "Spec.," ,-i 1 ). According to the
Specification, the method results in "suppressing the formation of leakage-
promoting defects in a crystal lattice following dopant implantation in the
lattice" (id. ,-i 4).
Claim 21, the sole independent claim on appeal, is reproduced from
page 20 of the Appeal Brief (Claims App.), with key limitations indicated in
italicized text, as follows:
21. During fabrication of a semiconductor device on a
crystal substrate, the semiconductor device having source and
drain regions, with a channel between the source and drain
regions and a gate conductor positioned above the channel, a
method for suppressing the formation of leakage-promoting
defects in a crystal lattice due to dopant implantation in the
lattice, comprising:
providing impurity atoms within the substrate, more
deeply than the source and drain regions within the lattice, the
impurity atoms being selected to impose a compressive stress
on the crystal lattice, at least some of the impurity atoms being
directly below at least part of the gate conductor;
implanting dopant atoms into the lattice; and
after implanting the dopant atoms into the lattice,
annealing the lattice to thereby cause compressive stress
exerted by the impurity atoms on the lattice, including those of
the impurity atoms directly below at least part of the gate
conductor, to emit interstitial defect atoms from a region
containing the impurity atoms.
DISCUSSION
The Examiner acknowledged that Yu does not explicitly disclose the
disputed limitations (identified above) of claim 21 (Final Act. 3--4). The
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Appeal2014-004110
Application 11/928,142
Examiner found, however, that Yu's Figures 1-7 describe the same structure
and fabrication process described in claim 21 and, therefore, the disputed
claims limitations would be inherent in the prior art (id. at 4). According to
the Examiner, Yu's "crystalline SiGe layer 3 comprising Ge atoms would
inherently impose a compressive stress on a crystalline Si layer 2 and/or a
crystalline Si layer 4 since Ge atoms are larger than Si atoms" (Ans. 3).
We agree with the Appellants (Appeal Br. 6, 7-9, 10, 14; Reply Brief
filed January 17, 2014 at 3-5) that the Examiner's inherency position is not
well-founded. As the Appellants point out (Appeal Br. 7), Yu's "thin,
strained lattice semiconductor layer 2 comprises a tensilely strained,
crystalline Si layer from about 50 to about 200 A thick, grown on a strain-
relaxed, graded composition Si-Ge buffer layer 3 several µm thick," which
"in tum [is] formed on a suitable substrate 4, e.g., a crystalline Si wafer or a
silicon-on-insulator (SOI) substrate" (col. 7, 11. 34--40) (emphases added).
Specifically, Yu teaches (col. 7, 11. 40--47) (emphasis added):
[W]hen the Si atoms of the strained lattice semiconductor layer
2 are deposited on the Si-Ge buffer layer 3 in alignment with
the greater lattice constant (spacing) of the Si and Ge atoms
therein, relative to pure Si, the deposited Si atoms tend to
"stretch" to align with the underlying lattice of Si and Ge
atoms, thereby "stretching" or tensilely straining Si layer 2.
Thus, as stated in the Second Declaration of Victor Moroz filed December 4,
2012 (,-i 9), Yu's Si-Ge buffer layer 3 is "strain-relaxed"-i.e., free from
internal stress (tensile or compressive). As for Yu's layer 2 or substrate 4,
the Examiner did not direct us to sufficient evidence indicating that
compressive stress-rather than tensile strain caused by stretching-would
necessarily be imparted to either of these elements. A mere conclusory
statement (Final Act. 4) that Yu's structure and fabrication process are
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Appeal2014-004110
Application 11/928,142
"substantially identical" to that recited in claim 21 is insufficient. In this
regard, the Examiner failed to establish, for example, that the specific
structure and annealing conditions described in Yu would inherently or
necessarily result in "compressive stress exerted by the impurity atoms on
the lattice, including those of the impurity atoms directly below at least part
of the gate conductor, to emit interstitial defect atoms from a region
containing the impurity atoms," as required by claim 21. In re Robertson,
169 F.3d 743, 745 (Fed. Cir. 1999) (inherency cannot be established by mere
probabilities or possibilities).
The rejection of claim 28, which depends from claim 21, is flawed for
an additional reason. Claim 28 recites that "the impurity atoms are all
disposed more deeply than source and drain regions within the lattice"
(Appeal Br. 21). As the Appellants point out (id. at 16), Yu's source and
drain regions 12 and 12', as shown in Figure 7, extend into layer 3
containing the impurity atoms (Ge). Therefore, the Examiner failed to
establish that Yu describes the further limitation recited in claim 28.
For these reasons, we cannot uphold the Examiner's rejection under
35 U.S.C. § 102(b) of claims 21-23 and 25-29 as anticipated by Yu.
REVERSED
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