Ex Parte TU

Patent Trials and Appeals Board

Jun 5, 2019

13914442 - (D) (P.T.A.B. Jun. 5, 2019)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
13/914,442 06/10/2013
160557 7590 06/07/2019
Innovation Counsel LLP
2890 Zanker Road
Suite 200
San Jose, CA 95134
FIRST NAMED INVENTOR
Ajin TU
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.
SMIC00051 US 1795
EXAMINER
NARAGHI, ALI
ART UNIT PAPER NUMBER
2895
NOTIFICATION DATE DELIVERY MODE
06/07/2019 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@innovationcounsel.com
docket@innovationcounsel.com
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PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte AJIN TU
Appeal2018-007247
Application 13/914,442
Technology Center 2800
Before LINDA M. GAUDETTE, CHRISTOPHER C. KENNEDY, and
SHELDON M. McGEE, Administrative Patent Judges.
GAUDETTE, Administrative Patent Judge.
DECISION ON APPEAL 1
The Appellant2 appeals under 35 U.S.C. § 134(a) from the Examiner's
decision finally rejecting claims 10, 11, and 13-20.3
We AFFIRM.
1 This Decision includes citations to the following documents: Specification filed
June 10, 2013 ("Spec."); Final Office Action dated Mar. 24, 2016 ("Final");
Appeal Brief filed Oct. 11, 2016 ("Appeal Br."); Examiner's Answer dated Aug.
10, 2017 ("Ans."); and Reply Brief filed Oct. 10, 2017 ("Reply Br.").
2 The Appellant is the Applicant, Semiconductor Manufacturing International
Corporation (Shanghai), also identified as the real party in interest. Appeal Br. 1.
3 We have jurisdiction under 35 U.S.C. § 6(b ).
Appeal2018-007247
Application 13/914,442
The invention relates to a method of manufacturing a semiconductor device
having an embedded silicon germanium (SiGe) source/drain region. Spec. 1:12-15.
The Examiner finally rejected the claims under 35 U.S.C. § I03(a) as
follows:
1. claims 10, 11, 13-15, 19, and 20 over Kwok et al. (US 2012/0181625
Al, pub. July 19, 2012) in view ofDruminski et al. (US 4,141,765, iss. Feb. 27,
1979);
2. claim 16 over Kwok in view ofDruminski4 and Wang (US
2008/0054347 Al, pub. Mar. 6, 2008); and
3. claims 1 7 and 18 over Kwok in view of Druminski and Kim et al. (US
2005/0266631 Al, pub. Dec. 1, 2005).
The Appellant's arguments in support of patentability of all appealed claims
are based on limitations in claim 10, the sole independent claim on appeal. See
generally Appeal Br. 1-7. Claim 10 is reproduced below.
10. A method for manufacturing a semiconductor device
compnsmg:
forming in a semiconductor substrate a trench used for a
source/drain region; and
forming a SiGe seed layer simultaneously on a sidewall and
bottom of the trench,
wherein the Si Ge seed layer on the sidewall of the trench has an
uneven thickness and has a maximum thickness at a location
corresponding to a channel region in the semiconductor substrate, and
4 We view the Examiner's failure to include Druminski in the statements of the
rejections of claims 16-18 as harmless error. See Final 5---6. It is clear from the
Appeal Brief that the Appellant understood all three grounds of rejection as based
on the combination of Kwok and Druminski. See Appeal Br. 1 (listing the grounds
of rejection).
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Appeal2018-007247
Application 13/914,442
wherein a ratio of the maximum thickness of the Si Ge seed
layer on the sidewall of the trench to the thickness of the Si Ge seed
layer on the bottom of the trench is in the range from about 1 :2.5 to
about 1: 1.
Id. at 9 (Claims Appendix).
The Examiner found Kwok discloses the invention as recited in claim 10,
with the exceptions that Kwok does not explicitly disclose (1) "forming a SiGe
seed layer simultaneously on a sidewall and bottom of the trench" ( claim 10
(emphasis added)), and (2) that "a ratio of the maximum thickness of the Si Ge seed
layer on the sidewall of the trench to the thickness of the Si Ge seed layer on the
bottom of the trench is in the range from about 1:2.5 to about 1:1" (id.). Final 3. As
to the simultaneous forming step, the Examiner found one of ordinary skill in the
art would have modified Kwok "so the seed layer on the bottom and the sidewall
of the trench are formed simultaneously, in order to shorten the process time;
therefore, increasing the productivity." Id. The Appellant does not dispute this
finding. See generally Appeal Br. 1-7. As to the thickness ratio, the Examiner
found one of ordinary skill in the art would have utilized a sidewall layer to trench
layer thickness ratio within the claimed range, based on Druminski' s disclosure
that 1: 1.2 is a suitable ratio for silicon growth rate on the trench walls and the
trench base. Final 3; see Druminski 5:15-25. As discussed in greater detail below,
the Appellant contends the Examiner reversibly erred with respect to this finding.
Appeal Br. 1-2.
The Appellant argues the Examiner's motivation for modifying Kwok to use
Druminski' s growth rate ratio is vague and conclusory, and is not supported by
factual findings. Appeal Br. 3--4. We are not persuaded by this argument for the
reasons stated by the Examiner in the paragraph bridging pages 4--5 of the Answer.
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Appeal2018-007247
Application 13/914,442
As noted above, the Appellant does not dispute the Examiner's finding that
modifying Kwok to simultaneously deposit the seed layer on the bottom and
sidewalls of the trench would shorten process time and increase productivity. Final
3; Ans. 4--5; see generally Appeal Br. 1-7. The Examiner found Druminski
discloses such a process wherein layers are simultaneously deposited on the bottom
and sidewalls of a trench. Final 8; Ans. 5. Druminski explicitly discloses the
growth rate ratio used during the simultaneous deposition process and states that
this ratio is desirable to suppress mound formation. See Druminski 5: 15-25. Thus,
although Kwok does not disclose a particular growth rate ratio, the Examiner had a
reasonable basis for finding that because Kwok suggests simultaneously depositing
layers on the bottom and sidewalls of a trench in a deposition method similar to
that used by Druminski, one of ordinary skill in the art would have understood that
Kwok utilizes a growth rate ratio similar to that used in Druminski' s method. Final
3; Ans. 4--5; see also Final 8 ("Understanding simple fluid mechanics would make
one realize that under simultaneous film deposition in the trench structure shown in
Kwok et al and Druminski et al, one would have more film deposited on the
bottom of the trench than the sidewalls of the trench.").
The Appellant argues that although Druminski discloses a growth rate ratio
of 1: 1.2, Druminski fails to teach the claimed thickness ratio of the Si Ge seed
layers on the trench sidewalls and the trench base because Druminski completely
fills the trough. Appeal Br. 2-3, 6. We are not persuaded by this argument for the
reasons explained by the Examiner on pages 3--4 and 7 of the Answer. We add the
following for completeness.
During examination, claim terms are given their broadest reasonable
construction consistent with the Specification. In re ICON Health & Fitness, Inc.,
496 F.3d 1374, 1379 (Fed. Cir. 2007). Thickness ratio is recited in the final
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Application 13/914,442
wherein clause of claim 10. Claim 10 is a method claim, and the final wherein
clause does not specify at what point in time during the method a ratio of the
maximum thickness of the Si Ge seed layer on the sidewall of the trench to the
thickness of the Si Ge seed layer on the bottom of the trench is in the range from
about 1 :2.5 to about 1: 1. In other words, claim 10 does not require that the final
product produced by the claimed method possess the claimed thickness ratio, only
that the ratio is present during some point in the method, e.g., at some point in time
during the step of simultaneously forming the Si Ge seed layer. As explained by the
Examiner, the final wherein clause of claim 10 reads on Druminski's process at
various times during deposition of a silicon layer, even though the trench is filled
at the completion of Druminski's process. Final 8; Ans. 3--4 ("[I]f one stops
[Druminski' s] process at any time before the trench is filled, then the thickness
ratio of the sidewall of the trench to the bottom of the trench would be 1: 1.2"). As
further explained by the Examiner, Druminski is relied on solely for a teaching of
the growth rate ratio used in Kwok' s method of forming a seed layer. Ans. 7; see
Final 3. The Appellant does not dispute the Examiner's finding that if Druminski's
growth rate ratio is used in Kwok's step of depositing a seed layer, a structure
having an SiGe seed layer with a maximum thickness on the trench sidewall to the
thickness on the bottom of the trench of 1: 1.2 would result. See generally Appeal
Br. 1-7.
We note the Appellant presents new arguments in support of patentability in
the Reply Brief relating to differences in the manner thickness is measured in
Druminski versus the claims. Reply Br. 4 ("In our application, the thicknesses of
the Si Ge seed layer 440 on the sidewall and the bottom of a trench are measured,
respectively, in a horizontal and a vertical direction .... [I]n Druminski, the
growth rates in the sloped side wall and the base of a trough are measured along a
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Application 13/914,442
direction parallel with the sloped side wall and a direction parallel with the base.").
We decline to consider these arguments because they are not directed to arguments
advanced by the Examiner for the first time in the Appeal Brief. See Ex parte
Borden, 93 USPQ2d 1473, 1474 (BPAI 2010) (informative) ("The reply brief is
not an opportunity to make arguments that could have been made during
prosecution, but were not. Nor is the reply brief an opportunity to make arguments
that could have been made in the principal brief on appeal to rebut the Examiner's
rejections, but were not").
In sum, the Appellant has not argued persuasively that the Examiner erred in
rejecting claims 10, 11, and 13-20. Accordingly, we sustain all three grounds of
rejection.
No time period for taking any subsequent action in connection with this
appeal may be extended under 3 7 C.F .R. § 1.13 6( a )(1 )(iv).
AFFIRMED
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