Ex Parte Cheshire et al

Patent Trial and Appeal Board

Aug 11, 2016

13455379 (P.T.A.B. Aug. 11, 2016)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR
13/455,379 04/25/2012 Alan Cheshire
44257 7590 08/15/2016
PATTERSON & SHERIDAN, LLP- - Applied Materials
24 Greenway Plaza, Suite 1600
HOUSTON, TX 77046
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.
014045/USACOl/AGS/ERS/PJT 1034
EXAMINER
KLUNK, MARGARET D
ART UNIT PAPER NUMBER
1716
NOTIFICATION DATE DELIVERY MODE
08/15/2016 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):
Pair_Eofficeaction@pattersonsheridan.com
psdocketing@pattersonsheridan.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte ALAN CHESHIRE and STANLEY DETMAR1
Appeal2015-001216
Application 13/455,379
Technology Center 1700
Before BRADLEY R. GARRIS, PETER F. KRATZ, and LILAN REN,
Administrative Patent Judges.
GARRIS, Administrative Patent Judge.
DECISION ON APPEAL
Pursuant to 35 U.S.C. § 134, Appellants appeal from the Examiner's
decision rejecting claims 1-20. We have jurisdiction under 35 U.S.C. § 6.
We AFFIRM.
Appellants claim a method for etching a feature in a silicon wafer
using an etch recipe that includes a plurality of etching steps, each etching
step comprising a cyclical etching substep and deposition substep, wherein
1 Applied Materials, Inc. is identified as the real party in interest. App.
Br. 3.
Appeal2015-001216
Application 13/455,379
an aspect ratio of the feature increases with a number of etching steps
performed over time, and adjusting a recipe variable of the etch recipe in
response to a current aspect ratio of the feature at each of the substeps
(independent claims 1 and 15).
A copy of representative claim 1, taken from the Claims Appendix of
the Appeal Brief, appears below.
1. A method for etching, comprising:
in a plasma processing chamber, etching a feature in a silicon layer using
an etch recipe that includes a plurality of etching steps until an end point is
reached, each etching step comprises a cyclical etching substep and
deposition substep wherein an aspect ratio of the feature increases with a
number of etching steps performed over time until the end point is reached;
and
adjusting a recipe variable of the etch recipe in response to a current
aspect ratio of the feature at each of the substeps, one etching substep
relative to another to manage thickness of sidewall polymers when the
feature becomes deeper to avoid closing the feature and preventing
subsequent etching.
The Examiner rejects claims 1-20 as follows:
independent claims 1 and 15 as well as dependent claims 2--4, 10, 11,
13, 14, 16, and 19 are rejected under 35 U.S.C. § 102(b) as anticipated by
Bhardwaj et al. (US 6,261,962 B 1, issued July 17, 2001) ("Bhardwaj 962")
as evidenced by Puech et al. (US 2005/0103749 Al, published May 19,
2005) ("Puech") (Final Action 2-5);
dependent claims 5-9, 12, 17, 18, and 20 are rejected under 35 U.S.C.
§ 103(a) as unpatentable over these references in combination with
additional prior art (id. at 5-10); and
claims 1-20 are provisionally rejected on the ground of nonstatutory
obviousness-type double patenting as unpatentable over claims 1, 3, 5, and
2
Appeal2015-001216
Application 13/455,379
9-12 of Application No. 12/696773 (now Patent No. 8,937,017 B2) in view
of Bhardwaj 962 (id. at 11-12).2
We sustain the above rejections for the reasons given in the Final
Action, the Answer, and below.
Appellants challenge the§ 102 rejection of the independent claims by
arguing that "Bhardwaj discloses ramping up and ramping down the
magnitude of various etching process parameters, but does not disclose
adjusting any of the parameters 'in response to a current aspect ratio' as
recited in claims 1 and 15" (App. Br. 7). In support of this argument,
Appellants rely on corresponding statements made in the Declaration of
record under 37 C.F.R. § 1.132 from Jon Farr (i.e., dated November 11,
2013) (id.). 3
In response, the Examiner points to the disclosure of Bhardwaj 962
that "it also can become progressively more difficult to deposit material as ..
. the aspect ratio increases" (Bhardwaj 962 col. 8, 11. 10-13) and that "[b ]y
controlling the amplitude of one or more of the [recipe variables such as] gas
flow rates, ... the system can be tuned in an appropriate manner to achieve
good anisotropic etching with proper sidewall passivation" (id. at 11. 13-17)
(Ans. 13-14). The Examiner interprets this disclosure to teach adjusting a
recipe variable in response to a current aspect ratio as claimed in the sense
that the current aspect ratio is known to be increased relative to the prior
2 The rejection of claims 1-20 on the ground of nonstatutory obviousness-
type double patenting as unpatentable over claims 1-20 of US Patent No.
8,298,959 to Bhardwaj in view of Bhardwaj 962 (id. at 11) has been
overcome by a terminal disclaimer (Ans. 16).
3 Appellants rely on this same fundamental argument in contesting each of
the rejections advanced in this appeal (id. at 7-12 and 14).
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Appeal2015-001216
Application 13/455,379
aspect ratio after each cyclical substep (id. at 14). Further, the Examiner
determines that it is reasonable and consistent with the Specification to
interpret the independent claims as encompassing such an adjusting step
because Appellants' disclosed step of adjusting a recipe variable "in
response to the current aspect ratio" (Spec. if 77) is described specifically
only in the sense that "as the aspect ratio continually increases over
subsequent cycles, one or more of the variables of the process recipe is
adjusted (e.g., ramped up or down) to maintain and/or optimize the etch
performance" (id.) (Ans. 14).
Appellants reply by contending that "Bhardwaj provides no indication
that the actual[] aspect ratio is known at any time" (Reply Br. unnumbered
2) and that "an approximation of an aspect ratio is not the same as an actual
current aspect ratio" (id. at unnumbered 4).
The deficiency of Appellants' contention is that the independent
claims merely recite "a current aspect ratio" without explicitly requiring a
ratio which is actual or excluding a ratio which is an approximation. In this
regard, we emphasize that Appellants do not identify any Specification
disclosure in support of the proposition that the independent claims must be
interpreted as requiring an actual rather than an approximate current aspect
ratio. Therefore, the record before us supports interpreting the independent
claims to encompass adjusting a recipe variable in response to an
approximation of a current aspect ratio (i.e., wherein the approximation
constitutes the current aspect ratio being increased compared to the prior
aspect ratio).
For the reasons stated above and given by the Examiner, we agree
with the Examiner's interpretations of Bhardwaj 962 as well as the
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Appeal2015-001216
Application 13/455,379
independent claims and concomitantly with the Examiner's finding that the
former anticipates the latter.
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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