Ex Parte Schier

Patent Trial and Appeal Board

Mar 17, 2017

12776110 (P.T.A.B. Mar. 17, 2017)

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.
12/776,110 05/07/2010 Herbert SCHIER V0216US 1544
91286 7590
Harness, Dickey & Pierce, P.L.C. (Lam)
P.O. Box 828
Bloomfield Hills, MI 48303
EXAMINER
PHAM, THOMAS T
ART UNIT PAPER NUMBER
1713
NOTIFICATION DATE DELIVERY MODE
03/21/2017 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):
s stevens @ hdp .com
troymailroom @hdp. com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte HERBERT SCHIER
Appeal 2015-001628
Application 12/776,110
Technology Center 1700
Before CATHERINE Q. TIMM, N. WHITNEY WILSON, and
CHRISTOPHER C. KENNEDY, Administrative Patent Judges.
WILSON, Administrative Patent Judge.
DECISION ON APPEAL
Appellant1 appeals under 35 U.S.C. § 134(a) from the Examiner’s May 7,
2013 decision finally rejecting claims 20—31 (“Final Act.”). We have
jurisdiction over the appeal under 35 U.S.C. § 6(b).
We affirm-in-part.
1 Appellants identify the Real Party in Interest as LAM Research AG
(Appeal Br. 1).
Appeal 2015-001628
Application 12/776,110
CLAIMED SUBJECT MATTER
Appellant’s invention is directed to a method for treating a substrate — in
particular stripping a photoresist — using an acid composition comprising a
mixture of sulfuric acid and periodic acid at a temperature of 110°—145°C by
dispensing the acid composition on the substrate which is mounted on a spinning
chuck for 1 to 5 minutes (Spec. 3, 9). Details of the claimed method are set forth
in Claim 20, as reproduced below from the Claims Appendix:
20. A method for treating a substrate, comprising:
spinning a chuck having the substrate mounted thereon;
and
dispensing a mixture of sulfuric acid and periodic acid
onto the substrate as the chuck is spinning, the mixture being at
a temperature in the range of 110°C to 145°C, such that a
dwell time of the process mixture on the substrate is from one
to five minutes;
wherein sulfuric acid is present in said mixture at a range
of 70-99.5 wt.% and periodic acid is present in said mixture at a
range of 0.1-10 wt.%, calculated as TEICE and H2SO4.
REJECTIONS
I. Claims 20-28 and 31 are rejected under 35 U.S.C. § 103(a) as
being unpatentable over Cooper2 in view of Tsung-Kuei.3
II. Claims 29 and 30 are rejected under 35 U.S.C. § 103(a) as
being unpatentable over Cooper in view of Tsung-Kuei, and further in view
of Yashima.4
2 Cooper et al., US 2009/0281016 Al, published November 12, 2009.
3 Tsung-Kuei, US 2003/0196986 Al, published October 23, 2003.
4 Yashima, US 2008/0124267 Al, published May 29, 2008.
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Application 12/776,110
DISCUSSION
Rejection I. With the exception of claim 31, Appellant argues all of
the claims subject to Rejection I together. Accordingly, we focus our analysis
on the rejection of claim 20, but address claim 31 separately.
The Examiner finds that Cooper teaches a method for treating a
semiconductor substrate, such as etching a photoresist layer on a wafer,
comprising contacting the substrate with a mixture of sulfuric acid and
periodic acid, the mixture being at a temperature in the range of 20°C to
200°C, for a period of 10 seconds to 60 minutes (Final Act. 2, citing Cooper,
17, 30, 31, 68, and 81). The Examiner implicitly, and correctly, finds that
the temperature range and contacting period disclosed in Cooper overlap with
the corresponding values in claim 20 and, therefore, those values would have
been obvious (Final Act. 2—3). The Examiner further finds that Cooper
discloses that the contact between the acid mixture and the substrate may be
accomplished in any suitable manner, and that the sulfuric acid may be
present at a concentration of about 99 wt% while the periodic acid may be
present at an amount of about 1 wt% (Final Act. 3, citing Cooper, H 34, 67,
75, and 79).
The Examiner also finds that Cooper is silent with regards to the
specific details of applying the acid mixture to the substrate (i.e. the claim
limitations describing a spinning chuck having the substrate mounted thereon)
{id.). The Examiner relies on the disclosure of Tsung-Kuei as teaching a
method of wet etching a layer on a semiconductor substrate using an etchant,
wherein the etchant is advantageously injected and form puddled on the
substrate while the substrate is rotated on a spin chuck to improve etch
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Application 12/776,110
uniformity, increase etch rate and reduce etchant consumption (Final Act. 3,
citing Tsung-Kuei, Abstract, || 6—9, and 75). The Examiner concludes that:
it would have been obvious to one of ordinary skill in the art at
the time the invention was made, in routine experimentations,
to use the method of Tsung-Kuei's as described above to etch
the photoresist layer of Cooper's by dispensing the above
mixture of sulfuric acid and periodic acid of Cooper's onto the
substrate mounted on a spinning chuck, wherein the mixture of
sulfuric acid and periodic acid is at a temperature in a range of
110-145°C and for a dwell time in the range of 1-5 minutes
because Cooper is silent about the specific details on
contacting the substrate with the mixture of sulfuric acid and
periodic acid by spraying in a single wafer apparatus, and
Tsung-Kuei teaches that such method advantageously improve
etch uniformity, increasing etch rate, and reducing etchant
consumption.
(Final Act. 3—4).
Appellant does not dispute that Cooper teaches a composition which
can contain both sulfuric and periodic acids in the requisite amounts, but
instead argues that Cooper’s specific disclosures for mixtures containing both
sulfuric and periodic acids fall outside the claimed temperature and contact
time ranges (Appeal Br. 2). In particular, Appellant contends that Cooper
discloses that mixtures of sulfuric and periodic acid are effective “at
temperatures between 60 and 95°C and reaction times of 30-60 minutes,
depending on type of implant, dose, and energy” (Appeal Br. 2, citing Cooper,
177). Therefore, according to Appellant, it would not have been obvious to
arrive at the claimed times and temperatures through routine optimization
(Appeal Br. 3).
“A prima facie case of obviousness may be made when the only
difference from the prior art is a difference in the range or value of a
particular variable. In re Peterson, 315 F.3d 1325, 1329 (Fed. Cir. 2003); In
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Application 12/776,110
re Woodruff, 919 F.2d 1575, 1578 (Fed. Cir. 1990); In re Kumar, 418 F.3d
1361, 1366 (Fed. Cir. 2005). Where “the difference between the claimed
invention and the prior art is some range or other variable within the claims
. . . , the [patentee] must show that the particular range is critical, generally
by showing that the claimed range achieves unexpected results . . . . ”
Woodruff, 919 F.2d at 1578 (internal citations omitted).
In this instance, Appellant has not shown reversible error in the
Examiner’s findings that Cooper discloses each of the components of the
claimed sulfuric acid/periodic acid mixture in amounts and at temperatures
which overlap (or completely encompass) the claimed ranges. In particular,
Cooper discloses the use of a composition for removing photoresist material
which includes at least one mineral acid and at least one oxidizing agent
(Cooper, Abstract). The mineral acid can be sulfuric acid (130) which can
be present in an amount from about 85 to about 99 wt% (1 34). The
oxidizing agent can be periodic acid (131) which can be present in an
amount from about 1 to about 15 wt% (134). The composition can be
contacted with the photoresist at a temperature from about 20° to about
200°C, and for a period of time from about 10 seconds to about 60 minutes
(1 68). Thus, the claimed compositional, temperature, and contacting time
ranges overlap with the disclosures of Cooper and, therefore, would have
been prima facie obvious in view of Cooper. Peterson, 315 F.3d at 1329.
In response, Appellant argues that “the disclosure of Cooper that is
particular to mixtures of sulfuric acid and periodic acid teaches that such
mixtures, at concentrations of 5-15% periodic acid, ‘are effective at removing
high-density implanted resist at temperatures between 60 and 95°C and
reaction times of 30-60 minutes, depending on type of implant, dose and
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Application 12/776,110
energy’” (Appeal Br. 2, citing Cooper 177). Because these temperature and
time ranges do not overlap with the claimed ranges, Appellant argues that they
would not have rendered the claimed ranges obvious (Appeal Br. 2—3). This
argument is not persuasive.
A prior art reference is analyzed from the vantage point of all that it
teaches one of ordinary skill in the art. See In re Lemelson, 397 F.2d 1006,
1009 (CCPA 1968) (“The use of patents as references is not limited to what
the patentees describe as their own inventions or to the problems with which
they are concerned. They are part of the literature of the art, relevant for all
they contain.”) Moreover, a reference is not limited to its preferred
embodiment, but must be evaluated for all of its teachings, including its
teachings of non-preferred embodiments. See In re Burckel, 592 F.2d 1175,
1179 (CCPA 1979). In this instance, that a single example/embodiment
describes ranges that fall outside the claimed ranges is not sufficient to
overcome the prima facie case of obviousness set forth by the Examiner.
Appellant also argues that the examples in the Specification show that
the claimed ranges show unexpected results which are sufficient to overcome
the prima facie case of obviousness (Appeal Br. 3). It is well settled that
Appellant has the burden of showing unexpected results. In re Freeman, 474
F.2d 1318, 1324 (CCPA 1973); In reKlosak, 455 F.2d 1077, 1080 (CCPA
1972). Such burden requires Appellant to proffer factual evidence that
actually shows unexpected results relative to the closest prior art (see In re
Baxter Travenol Labs., 952 F.2d 388, 392 (Fed. Cir. 1991)), and that is
reasonably commensurate in scope with the protection sought by claim 34 on
appeal (In re Grasselli, 713 F.2d 731, 743 (Fed. Cir. 1983); In re Clemens,
622 F.2d 1029, 1035 (CCPA 1980); In re Hyson, 453 F.2d 764, 786 (CCPA
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Application 12/776,110
1972)). The extent of the showing relied upon by Appellant must reasonably
support the entire scope of the claims at issue. See In re Harris, 409 F.3d
1339, 1344 (Fed. Cir. 2005).
In this instance, in the Appeal Brief, Appellant refer to the existence of
the experimental data set forth on pages 10-20 of the Specification, and quote
a short conclusion from the Specification:
As can be seen, in the lower temperature range of the
comparative art [(Cooper),] there was incomplete removal,
redeposition, precipitation and wafer spoilage. In contrast, the
elevated temperatures of the technology of the present
application achieve complete resist removal at reduced
treatment times.
(Appeal Br. 3). Appellant’s failure to provide an explanation in the Appeal
Brief how the data allegedly demonstrates unexpected results is sufficient for
us to conclude that Appellant has not met its burden to overcome the prima
facie case of obviousness. See, e.g., 37 C.F.R. § 41.41 (b)(2):
Any argument raised in the reply brief which was not raised in
the appeal brief, or is not responsive to an argument raised in
the examiner’s answer, including any designated new ground of
rejection, will not be considered by the Board for purposes of
the present appeal, unless good cause is shown.
Nevertheless, the Examiner reviewed the data in the passages of the
Specification cited by Appellant and determined that it did not overcome the
prima facie case of obviousness (Ans. 7—8). Among other deficiencies in the
data, the Examiner finds that the data does not show improved results for
compositions containing different concentrations of the components, or which
have different dwell times on the substrate (Ans. 9). Appellant does not
persuasively dispute this finding. Because the burden rests with Appellant to
establish that the supplied evidentiary showing is commensurate in scope with
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Application 12/776,110
the claimed subject matter, the failure to do requires us to reject the proposed
showing of unexpected results. See Klosak, 455 F.2d at 1080.
Appellant also argues that Tsung-Kuei’s etching technique requires a
long contact time (20-30 minutes) between the substrate and the acid solution
(Appeal Br. 4, citing Tsung-Kuei, 9, 18, and Table 1). Therefore,
according to Appellant, the combined disclosures of Tsung-Kuei and Cooper
“is entirely inconsistent with the process parameters recited in claim 20, and,
in particular ... a dwell time of the process mixture on the substrate . . . from
one to five minutes” (Appeal Br. 4). This argument is not persuasive,
essentially for the reasons set forth at page 9 of the Answer, namely that
Cooper discloses dwell times (10 seconds to 60 minutes) which overlap with
the claimed times, and that a detailed evaluation of Cooper’s disclosure
suggests a dwell time of 1 minute for single wafer processing (Ans. 9).
Thus, we conclude that, based on the evidence of record, Appellant has
not shown reversible error in the rejection of claim 20 over Cooper in view of
Tsung-Kuei.
Appellant separately argues claim 31, which recites that the spinning of
the substrate and the dispensing of the acid mixture are controlled to produce
a shear flow rate of approximately 1.5 liters/min across the substrate. The
Examiner finds that this limitation is suggested by Tsung-Kuei, which teaches
injecting the etchant at a flow rate of 0.6—5 liters/min for 3 seconds while
spinning the wafer at 0-50 rpm, which means that the shear flow rate for at
least the point of contact is 0.6—5 liters per minute. We agree with Appellant
that construing the term “shear flow rate” in claim 31 to cover the short period
that the etchant is dispersed onto the substrate in Tsung-Kuei is not reasonable
in light of the claim language, which suggests that the shear flow rate should
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Application 12/776,110
be measured over the course of the entire dwell time. Thus, we determine that
the Examiner’s findings with respect to the shear flow rate of Tsung-Kuei do
not support a finding of obviousness, and reverse the rejection of claim 31.
Rejection II.
Rejection II is directed to claims 29 and 30, which recite the recycling
of the mixture of sulfuric and periodic acids (claim 30 recites recycling by
reoxidizing the mixture with ozone). The Examiner finds that Yashima
teaches a method to recycle waste by-products from etching of a substrate
with an etchant, so that the by-products may be recycled to be used as the
etchant again, and that the recycling prevents adverse effects on the
environment (Final Act. 5, citing Yashima, H 5—24). Based on the disclosure
in Yashima and Cooper’s teaching that periodic acid may be generated in site
by oxidizing an iodine compound with ozone, the Examiner concludes that it
would have been obvious to recycle the periodic acid using ozone in order to
prevent adverse environmental effects (Final Act. 5—6).
Appellant argues that Yashima does not disclose using the recycled
waste by-products in the original products and, therefore, that it does not
support the Examiner’s obviousness conclusion (Appeal Br. 5). This
argument is not persuasive. As noted by the Examiner, the clear use of a
recycled product is to use it, and Cooper discloses recycling the etching
composition (Ans. 10, citing Cooper, 171). As held by the Supreme Court,
“[a] person of ordinary skill is also a person of ordinary creativity, not an
automaton.” KSRInt’l Co. v. Teleflex, Inc., 550 U.S. 398, 421 (2007). In
view of this holding, the preponderance of the evidence supports the
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Examiner’s determination that recycling of the mixture would have been
obvious in light of the combined teachings of the prior art.
CONCLUSION
We AFFIRM the rejection of claims 20-28 under 35 U.S.C. § 103(a)
as being unpatentable over Cooper in view of Tsung-Kuei.
We REVERSE the rejection of claim 31 over Cooper in view of
Tsung-Kuei.
We AFFIRM the rejection of claims 29 and 30 under 35 U.S.C. § 103(a)
as being unpatentable over Cooper in view of Tsung-Kuei, and further in view
of Yashima.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R.
§ 1.136(a)(l)(iv).
AFFIRMED-IN-PART
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