ASML Netherlands B.V.

Patent Trials and Appeals Board

May 24, 2021

2020002622 (P.T.A.B. May. 24, 2021)

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.
15/557,802 09/12/2017 Hakki Ergün CEKLI 081468-0454130 7364
909 7590 05/24/2021
Pillsbury Winthrop Shaw Pittman, LLP
PO Box 10500
McLean, VA 22102
EXAMINER
RIDDLE, CHRISTINA A
ART UNIT PAPER NUMBER
2882
NOTIFICATION DATE DELIVERY MODE
05/24/2021 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_ip@pillsburylaw.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte HAKKI ERGUN CEKLI, XING LAN LIU,
STEFAN CORNELIS THEODORUS VAN DER SANDEN, and
RICHARD JOHANNES FRANCISCUS VAN HAREN
Appeal 2020-002622
Application 15/557,802
Technology Center 2800

Before THU A. DANG, JAMES R. HUGHES, and CARL L. SILVERMAN,
Administrative Patent Judges.

DANG, Administrative Patent Judge.

DECISION ON APPEAL
STATEMENT OF THE CASE
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s decision to reject claims 1–14, and 16–20. See Final Act. 2–7.
The Examiner indicates that claim 15 contains allowable subject matter. Id.
We have jurisdiction under 35 U.S.C. § 6(b).
We REVERSE.

1 We use the term “Appellant” to refer to “applicant” as defined in 37 C.F.R.
§ 1.42. Appellant identifies the real party in interest as ASML Netherlands
B.V. Appeal Br. 2.
Appeal 2020-002622
Application 15/557,802
2
CLAIMED SUBJECT MATTER
According to Appellant, the invention relates to “a method of
controlling a lithographic process,” and in particular, to “a method for
reducing overlay errors on a substrate by processing data relating to sub-
fields of a field.” Spec. ¶ 2. Claim 1, reproduced below, is illustrative of the
claimed subject matter:
1. A lithographic method comprising:
obtaining data about an exposure field;
processing the data relating to a sub-field of the field
using a model parameterized just to the sub-field to produce sub-
field correction information; and
correcting exposure of the sub-field using the
sub-field correction information.
REFERENCES
The prior art relied upon by the Examiner is:
Name Reference Date
Padiy US 2011/0205511 A1 Aug. 25, 2011
Chung US 2010/0110401 A1 May 6, 2010
REJECTIONS
Claims 1–12 are rejected under 35 U.S.C. § 102(a)(1) as anticipated
by Padiy. Final Act. 2. Claims 13, 14, and 16–20 are rejected under 35
U.S.C. § 103 as being obvious over Padiy in view of Chung. Final Act. 5.
OPINION
A. Claims 1–12 are rejected under 35 U.S.C. § 102(a)(1) as being
anticipated by Padiy.
Appellant argues that the cited portions of Padiy do not disclose “a
model parameterized just to the sub-field to produce sub-field correction
information,” as claimed. Appeal Br. 5. According to Appellant, “there is
Appeal 2020-002622
Application 15/557,802
3
no apparent disclosure in the cited portions of Padiy of the claimed sub-field
of [an exposure] field,” but rather, “the intra-field reference grid appears to
describe the entire field, not a sub-portion of it.” Id. at 7. That is, “rather
than describing a part of the [exposure] field less than all of the field, i.e., a
sub-field, the cited portions of Padiy appear to describe that the grid should
be dense enough to encompass all possible distortions across the entire
field.” Id. (citing Padiy ¶ 85).
Although the Examiner points out that “[t]he claim language does not
define ‘an exposure field’” for the “sub-field,” and construes that, “under the
broadest reasonable interpretation of ‘an exposure field,’ the exposed surface
of the substrate includes multiple fields” (Advisory Act. (Cont’n Sheet)),
Appellant argues that such claim construction is “unreasonable.” Appeal Br.
7. According to Appellant, “‘[a]n exposure field’ is a known term in the art
that refers to an area of a substrate exposed in a shot (in the case of a
stepper) and/or after an exposure scan (in the case of a scanner).” Id. at 7–8
(citing www.lithoguru.com/scientist/glossary/F.html#exposure–field
(“Field, Exposure The area of a wafer that is exposed at one time by the
exposure tool.”)). Appellant points out that even “Padiy refers explicitly to
an ‘exposure field’ and makes clear that it is related to each of multiple
portions of a substrate, rather than an entire exposed surface of the
substrate.” Id. at 8 (citing Padiy ¶¶ 41–42). Thus, Appellant contends that
“a person of ordinary skill in the art would not consider, having regard to the
specification or knowledge in the art, an exposed substrate surface of
multiple fields as an exposure field.” Id.
We have considered all of Appellant’s arguments and evidence
presented. We agree with Appellant that the preponderance of the evidence
Appeal 2020-002622
Application 15/557,802
4
on this record does not support the Examiner’s finding that claim 1 is
anticipated by Padiy.
The claimed invention relates to a method for “reducing overlay errors
on a substrate by processing data relating to sub-fields of a field.” Spec. ¶ 2.
In particular, the invention provides a method of dividing an exposure field
into sub-fields in order to optimize the lithographic process. Spec. ¶¶ 66–68.
Figure 8 of the invention is reproduced below.

Figure 8, reproduced above, shows exemplary wafer 800 divided into
a number of exposure fields 802. Spec. ¶¶ 66–68. As shown in Figure 8,
each exposure field, e.g. 802, 806, and 810, are divided into sub-fields, e.g.
804, 808, and 814, respectively. Id. Accordingly, representative claim 1
recites, “processing the data relating to a sub-field of the field using a model
Appeal 2020-002622
Application 15/557,802
5
parameterized just to the sub-field to produce sub-field correction
information,” and “correcting exposure of the sub-field using the
sub-field correction information.”
On the record before us, we are persuaded by Appellant’s contention
that the cited portions of Padiy relied on by the Examiner do not disclose “a
model parameterized just to the sub-field to produce sub-field correction
information,” as claimed. Appeal Br. 5.
The Examiner relies on Padiy, which states “the exposure grid may be
parameterized also by letting the intra-field parameters vary from field to
field in order to account for the possible variation of the intra-field
fingerprint from field to field (e.g., due to wafer grid deformation).” See
Padiy ¶ 85 (cited at Ans. 5). We agree with Appellant that “there is no
apparent disclosure in the cited portions of Padiy of the claimed sub-field of
[an exposure] field,” as required for an anticipation rejection, but rather, in
these cited portions, “the intra-field reference grid appears to describe the
entire field, not a sub-portion of it.” Appeal Br. 7.
Although the Examiner construes that, “under the broadest reasonable
interpretation of ‘an exposure field,’ the exposed surface of the substrate
includes multiple fields” (Advisory Act. (Cont’n Sheet)), we agree with
Appellant that such construction is “unreasonable.” See Appeal Br. 7. That
is, the claims must be “given their broadest reasonable interpretation
consistent with the specification.” See Phillips v. AWH Corp., 415 F.3d
1303, 1316, (Fed. Cir. 2005) (emphasis added). Here, the Examiner’s
finding of an “exposure field” as including “multiple fields” (Advisory Act.
(Cont’n Sheet)) is unreasonable in view of the Specification, which
describes a method of dividing an exposure field into sub-fields in order to
optimize the lithographic process. See, for example, Spec. ¶¶ 66–68, Fig. 8.
Appeal 2020-002622
Application 15/557,802
6
Consequently, we are constrained by the record before us to find that
the Examiner erred in finding Padiy anticipates Appellant’s claim 1.
Independent claim 12 includes limitations of commensurate scope, and thus,
also stands with claim 1. Dependent claims 2–11 depend on claim 1, and
thus, stand therewith. Accordingly, we do not sustain the Examiner’s
anticipation rejection of claims 1–12 over Padiy.
B. Claims 13–14 and 16–20 are rejected under 35 U.S.C. § 103 as being
obvious over Padiy in view of Chung.
The Examiner does not suggest, and has not established on this
record, that the additionally cited Chung reference overcomes the
aforementioned deficiencies of Padiy. See Final Act. 5–7. Consequently,
we are constrained by the record before us to find that the Examiner also
erred in concluding that the combination of Padiy and Chung renders
obvious Appellant’s dependent claims 13, 14, and 16–20 depending from
independent claim 12.
CONCLUSION
We reverse the Examiner’s rejections of claims 1–12 under 35 U.S.C.
§ 102(a)(1) and of claims 13, 14, and 16–20 under 35 U.S.C. § 103.
DECISION SUMMARY
Claim(s)
Rejected
35 U.S.C. § Reference(s)/Basis Affirmed Reversed
1–12 102(a)(1) Padiy 1–12
13, 14, 16–
20
103 Padiy, Chung 13, 14, 16–
20
Overall
Outcome
1–14, 16–20

REVERSED