Ex Parte Willson et al

Patent Trial and Appeal Board

Mar 8, 2018

14242223 (P.T.A.B. Mar. 8, 2018)

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.
TEXAS-17767 5807
EXAMINER
CHACKO DAVIS, DABORAH
ART UNIT PAPER NUMBER
1722
MAIL DATE DELIVERY MODE
14/242,223 04/01/2014
23535 7590 03/09/2018
MEDLEN & CARROLL, LLP
1440 Broadway
SUITE 1010
Oakland, CA 94612
C. Grant Willson
03/09/2018 PAPER
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.
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte C. GRANT WILLSON, WEJ-LUN KANE JEN,
BRANDON MARK RAWLINGS, and
JEFFREY RYAN STRAHAN
Appeal 2017-003589
Application 14/242,223
Technology Center 1700
Before KAREN M. HASTINGS, DEBRA L. DENNETT, and
MERRELL C. CASHION, JR., Administrative Patent Judges.
HASTINGS, Administrative Patent Judge.
DECISION ON APPEAL
Appellant1 appeals under 35 U.S.C. § 134(a) from the Examiner’s
rejection under 35 U.S.C. § 103(a) of claims 1—7 as unpatentable over at
least the combined prior art of Hinsberg, III, et al., (US 4,767,723 issued
Aug. 30, 1988; hereinafter “Hinsberg”), Taylor et al., (US 5,087,547 issued
Feb. 11, 1992; hereinafter “Taylor”), Endo et al., (US 2003/0082926 Al,
published May 1, 2003; hereinafter “Endo”) and Cheng et al., (US 5,501,926
issued Mar. 26, 1996; hereinafter “Cheng”).2 We have jurisdiction over the
appeal under 35 U.S.C. § 6(b).
1 Appellant is Board of Regents, The University of Texas System, also
identified as the real party in interest (Appeal Br. 3).
2 The Examiner further applies Lee (US 7,449,538 B2; issued Nov. 11,
2008) to dependent claim 2 (e.g., Final Action 5).
Appeal 2017-003589
Application 14/242,223
We AFFIRM.
Independent claim 1 below is illustrative of the subject matter on
appeal:
1. A method of making two patterns in one layer of photoresist,
comprising the steps of:
(a) providing a substrate, a dual-tone photoresist, a source of
radiation, and a two-tone mask, said mask having transparent areas, opaque
areas and areas transparent to selective wavelengths of radiation, wherein
said photoresist comprises a thermally activated, chemically amplified
crosslinker and a photoacid generator;
(b) forming one or more thin layers over said substrate;
(c) coating the top layer with said dual-tone photoresist;
(d) exposing said photoresist to radiation, said radiation coming from
said source of radiation and passing through said mask, said mask positioned
on top of said photoresist under conditions such that two patterns are
generated in said layer of photoresist, said patterns defined by i) radiation-
exposed regions of the photoresist having a positive tone response, ii)
unexposed regions of the photoresist, and iii) at least one radiation-exposed
region of the photoresist capable of a negative tone response; and
e) exposing said at least one radiation-exposed region of the
photoresist capable of a negative tone response to heat wherein a negative
tone response is achieved.
Independent claim 3 is similar to claim 1, but also recites additional
steps f) and g) inclusive of a reactive ion etching. (Claims Appendix, Appeal
Br. 13-143).
3 Herein, we refer to the Specification filed Apr. 1, 2014 (“Spec.”); Final
Office Action, mailed Mar. 6, 2015 (“Final Action”); Appeal Brief, filed Jul.
13, 2015 (“App. Br.”); the Examiner’s Answer, mailed Dec. 2, 2015
(“Ans.”); and the Reply Brief, filed Feb. 2, 2016 (“Reply Br.”).
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Appeal 2017-003589
Application 14/242,223
ANALYSIS
Upon consideration of the evidence on this record and each of
Appellant’s contentions, we find that the preponderance of evidence
supports the Examiner’s conclusion that the subject matter of Appellant’s
claims is unpatentable over the applied prior art. We sustain the Examiner’s
§ 103(a) rejections essentially for the reasons set out by the Examiner in the
Final Action and the Answer.
We add the following primarily for emphasis.
It has been established that “the [obviousness] analysis need not seek
out precise teachings directed to the specific subject matter of the challenged
claim, for a court can take account of the inferences and creative steps that a
person of ordinary skill in the art would employ.” KSR Int 7 Co. v. Teleflex
Inc., 550 U.S. 398, 418 (2007). Likewise, it is also well settled that a
reference stands for all of the specific teachings thereof as well as the
inferences one of ordinary skill in the art would have reasonably been
expected to draw therefrom. See In re Fritch, 972 F.2d 1260, 1264—65 (Fed.
Cir. 1992).
Hinsberg describes a dual-tone photo resist composition and process
containing two photoactive additives, one that accelerates dissolution upon
radiation and one that decelerates it (col. 2,11. 44—50). The resist
compositions are made sensitive to various wavelengths of UV light (col. 2,
11. 62—65). The photo resist may be diazonaphthoquinone-novolac
“commonly used in microcircuit fabrication” (Hinsberg col. 3,11. 5—8). As
the Examiner points out, Appellant likewise uses a novolac resin and
diazonaphthoquinone resist composition (e.g., Spec. 3:10—13; Ans. 7, 8).
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Application 14/242,223
Taylor likewise uses a similar novolac resist material, as does Cheng (Taylor
col. 2,11. 46-53; Cheng col. 5,11. 34—61).
Appellant’s main argument is that Hinsberg teaches use of an azide
material as the decelerant and that this would render the composition
incapable of being subject to plasma or reactive ion etching (Appeal Br. 6, 7;
Reply Br. 2). Appellant also contends that Taylor does not record two latent
images in a single pass and one cannot select out UV radiation with heat
from Taylor since Hinsberg does not have the “correct chemistry” (that is,
“no thermally active crosslinker”) to respond to heat (Reply Br. 4; see also
Appeal Br. 9). Appellant relies upon the Willson Declaration in support of
these arguments (e.g., Appeal Br. 6, 7).
Appellant’s arguments are not persuasive of reversible error as they
do not adequately consider the applied prior art as a whole. Hinsberg
describes a dual tone photo resist patterning process that, contrary to
Appellant’s position, is not limited to a resist composition that contains an
azide decelerant; an azide decelerant is merely described as a “preferred”
decelerant (Hinsberg col 2,11. 57—61; compare claim 1 with claim 2 of
Hinsberg). Merck & Co. v. Biocraft Labs., Inc., 874 F.2d 804, 807 (Fed.
Cir. 1989) (preferred embodiments are not controlling; all disclosures of the
prior art, including unpreferred embodiments, must be considered). Thus,
neither Appellant nor the Willson Declaration adequately address the
breadth of Hinsberg’s teachings. The Examiner also aptly points out that
claim 1 does not even require a reactive etch step (e.g., Ans. 6). In re Self,
671 F.2d 1344, 1348 (CCPA 1982) (It is well established that limitations not
appearing in the claims cannot be relied upon for patentability).
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Application 14/242,223
Thus, Appellant has not shown reversible error in the Examiner’s
determination that it would have been prima facie obvious to one of ordinary
skill in the art, using no more than ordinary creativity, to use a heat activated
crosslinker and a photoacid generator for their benefits as exemplified in
Endo and a heating step as exemplified in Taylor (and Endo) in Hinsberg’s
process, as each is a known element or step being used for its known
function in developing a photoresist material (see, e.g., Final Action 2-4;
Ans. 7—10). KSR Inti, 550 U.S. at 417 (2007)(It is a well-established
principle that, for an improvement to be patentable, it must be more than the
predictable use of prior art elements according to their established
functions); also id. at 418; see also id. at 421 (“A person of ordinary skill is
also a person of ordinary creativity, not an automaton.”); Ball Aerosol &
Specialty Container, Inc. v. Limited Brands, Inc., 555 F.3d 984, 993 (Fed.
Cir. 2009) (Under the flexible inquiry set forth by the Supreme Court, the
PTO must take account of “the inferences and creative steps,” as well as
routine steps, that an ordinary artisan would employ.)
Claim 7 (dependent on claim 1 via claims 5 and 6), and independent
claim 3 each recite a reactive ion etching step. The Examiner relies upon
Cheng to exemplify that reactive ion etching is a known alternative process
to wet etching or sputter etching procedures in developing a novolac dual
tone photoresist pattern after two latent images are formed in the dual tone
photoresist (Ans. 9). Appellant has not shown reversible error in the
Examiner’s determination that one of ordinary skill, using no more than
ordinary creativity, would have also used such a reactive ion etching step in
the Hinsberg/Taylor/Endo combination (see, e.g., Ans. 9—10). In re Keller,
642 F.2d 413, 425 (CCPA 1981) (“The test for obviousness is not whether
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Application 14/242,223
the features of a secondary reference may be bodily incorporated into the
structure of the primary reference. . . . Rather, the test is what the combined
teachings of [those] references would have suggested to those of ordinary
skill in the art.”); In reNievelt, 482 F.2d 965, 968 (CCPA 1973)
(“Combining the teachings of references does not involve an ability to
combine their specific structures.”).
Appellant does not separately argue any other claims, including
separately rejected claim 2.
Accordingly, we affirm the Examiner’s prior art rejections of the
claims under 35 U.S.C. § 103(a) for the reasons given above and presented
by the Examiner.
DECISION
The Examiner’s § 103(a) rejections are 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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