CARL ZEISS SMT GMBH

Patent Trials and Appeals Board

Mar 27, 2020

13790443 - (D) (P.T.A.B. Mar. 27, 2020)

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.
13/790,443 03/08/2013 Olaf Rogalsky 23375-0007001 5451
26161 7590 03/27/2020
FISH & RICHARDSON P.C. (BO)
P.O. BOX 1022
MINNEAPOLIS, MN 55440-1022
EXAMINER
ALLEN, STEPHONE B
ART UNIT PAPER NUMBER
2872
NOTIFICATION DATE DELIVERY MODE
03/27/2020 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):
PATDOCTC@fr.com
PTOL-90A (Rev. 04/07)

UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte OLAF ROGALSKY, SONJA SCHNEIDER, BORIS BITTNER,
JENS KUGLER, BERNHARD GELLRICH, and ROLF FREIMANN
Appeal 2018-007068
Application 13/790,443
Technology Center 2800
Before LARRY J. HUME, JUSTIN BUSCH, AND
MATTHEW J. MCNEILL, Administrative Patent Judges.
HUME, Administrative Patent Judge.
DECISION ON APPEAL
Pursuant to 35 U.S.C. § 134(a), Appellant,1 Carl Zeiss SMT GmbH,
appeals from the Examiner’s decision rejecting claims 1–12, 14–21,
and 30–32, which are all claims pending in the application. Appellant has
withdrawn claims 13 and 22–29 from consideration, and are not a subject of
this Appeal. Appeal Br. 1. We have jurisdiction under 35 U.S.C. § 6(b).
We AFFIRM IN PART.

1 We use the word “Appellant” to refer to “applicant” as defined in 37
C.F.R. § 1.42(a). Appellant identifies the real party in interest as Carl Zeiss
SMT GmbH. Appeal Br. 1.
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STATEMENT OF THE CASE2
The claims are directed to an imaging optical system for
microlithography. See Spec. (Title). In particular, Appellant’s disclosed
embodiments and claimed invention “relate[] to an imaging optical system,
in particular a projection objective, for microlithography, including optical
elements configured to guide electromagnetic radiation in an imaging beam
path for imaging an object field into an image plane.” Spec. 1, ll. 14–16.
Claims 1, 19, and 20, reproduced below, are representative of the
subject matter on appeal (emphases added to contested limitations):
Exemplary Claims
1. An imaging optical system, comprising:
optical elements configured to guide electromagnetic
radiation with a wavelength λ in an imaging beam path to
image an object field into an image field, the optical elements
comprising a first optical element,
wherein:
the imaging optical system has a pupil with first
and second coordinates;
the image field has first and second coordinates;
the image field and the pupil span an extended 4-
dimensional pupil space having the first and second

2 Our decision relies upon Appellant’s Appeal Brief (“Appeal Br.,” filed
Dec. 4, 2017); Reply Brief (“Reply Br.,” filed June 29, 2018); Examiner’s
Answer (“Ans.,” mailed May 10, 2018); Final Office Action (“Final Act.,”
mailed July 14, 2017); and the original Specification (“Spec.,” filed
Mar. 8, 2013) (claiming benefit of PCT/EP2011/004744 filed
Sept. 22, 2011, US 61/514,987 filed Aug. 4, 2011, and US 61/388,081, filed
Sept. 30, 2010). An oral hearing was conducted March 17, 2020, for which a
transcript will be made of record in due course.
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coordinates of the pupil and the first and second
coordinates of the image field;
during use of the imaging optical system, a
wavefront of the electromagnetic radiation passing
through the imaging optical system is defined as a
function of the extended 4-dimensional pupil space;
the first optical element has a non-rotationally
symmetrical surface with a two-dimensional surface
deviation relative to every rotationally symmetrical
surface;
the two-dimensional surface deviation has a
difference between its greatest elevation and its deepest
valley of at least λ;
for each point of the object field, a sub-aperture
ratio of the non-rotationally symmetrical surface deviates
by at least 0.01 from a sub-aperture ratio of every other
surface of the optical elements at the point of the object
field;
the non-rotationally symmetric surface of the first
optical element is configured so that, by displacing the
first optical element relative to the other optical elements,
a change to the wavefront occurs;
the change to wavefront has a portion with at least
2-fold symmetry;
a maximum value of the wavefront change in the
extended 4-dimensional pupil space is at least 1 x 10-5 of
the wavelength λ; and
the imaging optical system is a microlithography
imaging optical system.
19. An imaging optical system, comprising:
optical elements configured to guide electromagnetic
radiation with a wavelength λ in an imaging beam path to
image an object field from an object plane into an image plane,
wherein:
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at least two of the optical elements have a non
mirror-symmetrical surface which deviates at at least one
point from each mirror-symmetrical surface by at least
λ/10;
at each point of the object field, sub-aperture ratios
of the non mirror-symmetrical surfaces deviate from each
other by at least 0.01; and
the imaging optical system is a microlithography
imaging optical system.
20. An optical element comprising a non mirror-
symmetrical surface configured to change a wavefront of
incoming radiation with a wavelength λ, the non mirror-
symmetrical surface deviating by at least 10 λ from each mirror
symmetrical surface at at least one point, the optical element
being configured to be used in a microlithography imaging
optical system having an object field that is mirror-symmetrical
to a plane that includes a scanning direction.
Prior Art
The Examiner relies upon the following prior art as evidence in
rejecting the claims on appeal:
Chan et al. (“Chan”) US 2010/0195075 A1 Aug. 5, 2010
Mann et al. (“Mann”) US 2012/0147347 A1 June 14, 2012
Kugler et al. (“Kugler”) WO 2009/043573 A1 Apr. 9, 2009
Rejections on Appeal
R1. Claim 20 stands rejected under 35 U.S.C. § 102(e) as being
anticipated by Mann. Final Act. 2.
R2. Claims 1–12, 14–18, 21, and 30–32 stand rejected under
35 U.S.C. § 103(a) as being unpatentable over Kugler. Final Act. 4.
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R3. Claims 19 and 20 stand rejected under 35 U.S.C. § 103(a) as
being unpatentable over Chan. Final Act. 14.
ISSUES AND ANALYSIS
In reaching this decision, we consider all evidence presented and all
arguments actually made by Appellant. To the extent Appellant has not
advanced separate, substantive arguments for particular claims, or other
issues, such arguments are waived. 37 C.F.R. § 41.37(c)(1)(iv).
For essentially the same reasons argued by Appellant, infra, we
reverse obviousness Rejection R2 of claims 1–12, 14–18, 21, and 30–32, and
also reverse obviousness Rejection R3 of claims 19 and 20.3 We highlight
and address specific findings and arguments regarding claims 1 and 19 for
emphasis.
However, we disagree with Appellant’s arguments with respect to
anticipation Rejection R1 of claim 20 and, unless otherwise noted, we
incorporate by reference herein and adopt as our own: (1) the findings and
reasons set forth by the Examiner in the action from which this appeal is
taken, and (2) the reasons and rebuttals set forth in the Examiner’s Answer
in response to Appellant’s arguments. We highlight and address specific
findings and arguments regarding claim 20 for emphasis as follows.

3 Because we agree with at least one of the dispositive arguments advanced
by Appellant, we need not reach the merits of Appellant’s other arguments.
See Beloit Corp. v. Valmet Oy, 742 F.2d 1421, 1423 (Fed. Cir. 1984)
(finding an administrative agency is at liberty to reach a decision based on “a
single dispositive issue”).
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1. § 102(e) Rejection R1 of Claim 20
Issue 1
Appellant argues (Appeal Br. 5–6; Reply Br. 1–2) the Examiner’s
rejection of claim 20 under 35 U.S.C. § 102(e) as being anticipated by Mann
is in error. These contentions present us with the following issue:
Did the Examiner err in finding the cited prior art discloses “[a]n
optical element comprising a non mirror-symmetrical surface” wherein, inter
alia, “the optical element [is] configured to be used in a microlithography
imaging optical system having an object field that is mirror-symmetrical to a
plane that includes a scanning direction,” as recited in claim 20?
Analysis
The Examiner finds Mann discloses the disputed limitation. Final
Act. 2–3 (citing Mann Fig. 25; ¶¶ 26, 29, 51, and 90).
In response, Appellant points out the Examiner relies upon two
different embodiments in Mann in setting forth the anticipation rejection.
In his rejection, the Examiner relied on Mann’s
disclosure at [0157]–[0159] and FIG. 25 to show a non mirror-
symmetrical surface deviating by at least 10 λ, from each mirror
symmetrical surface at at least one point. But the embodiment
disclosed at those portions of Mann has an object field that is
non-mirror symmetrical with respect to a plane that includes a
scanning direction. While still pointing to FIG. 25, the
Examiner jumped to a different embodiment at paragraph
[0090] for the claimed feature. . . . As a result, the Examiner
failed to establish that Mann discloses an optical element that
meets all the claim limitations recited in claim 20. Hence, the
Examiner has not properly established that Mann discloses the
subject matter covered by claim 20.
Appeal Br. 6
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Our reviewing court holds that, in an anticipation rejection, “it is not
enough that the prior art reference . . . includes multiple, distinct teachings
that [an] artisan might somehow combine to achieve the claimed invention.”
Net MoneyIN, Inc. v. VeriSign, Inc., 545 F.3d 1359, 1371 (Fed. Cir. 2008).
Rather, the reference must “clearly and unequivocally disclose the claimed
[invention] or direct those skilled in the art to the [invention] without any
need for picking, choosing, and combining various disclosures not directly
related to each other by the teachings of the cited reference.” Id. (quoting In
re Arkley, 455 F.2d 586, 587 (CCPA 1972)). Thus, while “[s]uch picking
and choosing may be entirely proper in the making of a 103, obviousness
rejection . . . it has no place in the making of a 102, anticipation rejection.”
Arkley, 455 F.2d at 587–88.
However, in the Answer, the Examiner addresses Appellant’s
argument, and clarifies the anticipation rejection by explicitly not relying
upon distinct embodiments in Mann.
Although [the] Examiner agrees that Mann’s paragraph [0090]
describes a different embodiment of FIG. 4–5, this different
embodiment need not be relied upon because FIG. 24 of the
applied embodiment shows the recited “an object field that is
mirror-symmetrical to a plane that includes a scanning
direction” in the broadest reasonable interpretation because
Mann’s FIG. 24 and 25 shows an object field 9 in object plane
11 that under the trivial identity projection into itself is mirror
symmetrical about the x axis at y=0 in the x–y plane of the
drawing sheet of FIG. 24, which x–y plane includes the
scanning direction.
In summary, it is not that claim 20 specifically recites the
object plane is mirror-symmetrical with itself, but that the scope
of claim 20 is reasonably interpreted as broad enough to include
Mann’s object field 9 of FIG. 24 and 25 that is mirror-
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symmetrical within the drawing sheet of FIG. 24 that is the
object plane 11 of FIG. 25 including the scanning direction.
Ans. 12 (footnotes omitted).
We determine the Examiner made a finding in the Answer, and the
burden then shifted to Appellant to rebut these findings. However, we find
Appellant did not respond to the Examiner’s specific finding in the Reply
Brief. See generally, Reply Br. 1–2.
Therefore, based upon the findings above, on this record, we are not
persuaded of error in the Examiner’s reliance on the cited prior art to
disclose the disputed limitation of claim 20, nor do we find error in the
Examiner’s resulting finding of anticipation.
Accordingly, we sustain the Examiner’s anticipation rejection of
independent claim 20.
2. § 103 Rejection R2 of Claims 1–12, 14–18, 21, and 30–32
Issue 2
Appellant argues (Appeal Br. 10–15; Reply Br. 2–4) the Examiner’s
rejection of independent claims 1, 18, 21, and 32 under 35 U.S.C. § 103(a)
as being obvious over Kugler is in error. These contentions present us with
the following issue:
Did the Examiner err in finding the cited prior art teaches or suggests
“[a]n imaging optical system” that includes “optical elements configured to
guide electromagnetic radiation with a wavelength λ in an imaging beam
path to image an object field into an image field, the optical elements
comprising a first optical element, wherein,” inter alia, “the two-
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dimensional surface deviation has a difference between its greatest elevation
and its deepest valley of at least λ,” as recited in claim 1? (emphasis added).
Analysis
The Examiner finds “Kugler does not specifically disclose the two-
dimensional surface deviation has a difference between its greatest elevation
and its deepest valley of at least λ” (Final Act. 5), but relies upon the holding
in Aller for the proposition that “where the general conditions of a claim are
disclosed in the prior art, discovering the optimum or workable ranges
involves only routine skill in the art.” Id. at 6 (citing In re Aller, 105 USPQ
233 (C.C.P.A. 1955)). Independent claims 18 and 32 recite the same
disputed limitation as claim 1, and the Examiner similarly relies upon the
holding in Aller in rejecting these claims under Rejection R2. The Examiner
also relies upon the holding in Aller in rejecting independent claim 21, but
that claim instead recites “the non-rotationally symmetrical surface having a
deviation of at least 500 λ in relation to each rotationally symmetrical
surface at at least one point.”
The Examiner sets forth a motivational reason to modify Kugler in the
manner suggested:
Therefore, it would have been obvious to an ordinarily
skilled artisan at the time of invention to discover the optimum
or workable ranges for a difference between a greatest elevation
and a deepest valley of a two-dimensional surface deviation,
and for the wavefront change in the extended 4-dimensional
pupil space so as to achieve compensation for image aberrations
sufficient to encompass the expected image aberration, such
that a difference between a greatest elevation and a deepest
valley of a two-dimensional surface deviation is at least λ and a
maximum value of the wavefront change in the extended 4-
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dimensional pupil space is at least 1 x 10-5 of the wavelength λ;
and to discover the optimum or workable ranges a sub-aperture
ratio of each of the surfaces of the optical elements for each
point of the object field ratio of the non-rotationally
symmetrical surface deviates by at least 0.01 from a sub-
aperture ratio of every other surface of the optical elements.
Final Act. 6–7.
Appellant contends “the Examiner did not properly establish it would
have been obvious to a person of ordinary skill in the art to modify Kugler in
the manner indicated by the Examiner to provide the subject matter covered
by independent claim 1” (Appeal Br. 13–14) and “the Examiner improperly
relied upon Aller, and made the conclusory statement that ‘the general
conditions of a claim are disclosed in the prior art.’ The Examiner simply
has not satisfied his burden to show that Kugler discloses the general
conditions of the claim.” Appeal Br. 14.
The Examiner responds by finding:
Kugler discloses that the aberration correction achieved from
rotating lenses with a non-rotationally symmetrical surface is
also achieved from rotating mirrors with a non-rotationally
symmetrical surface as discussed above. Thus, as set forth in
paragraphs 10–13 of the [Final Action] from which appeal is
taken, Kugler discloses the general conditions of claim 1 under
In re Aller, and it would have been obvious to an ordinarily
skilled artisan at the time of invention to discover the relevant
optimum or workable ranges.
Ans. 19. We are not persuaded by the Examiner’s analysis.
We are not persuaded because the Examiner has not, by a
preponderance of evidence, demonstrated that adjusting various mirror
parameters or rotational symmetries (or non-symmetries) in Kugler would
have led an ordinarily skilled artisan to the claimed invention, nor has the
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Examiner established by evidence or analysis that any of the mirror
parameters or orientations available to Kugler are result-effective variables
that would have led an ordinarily skilled artisan to a decision to implement a
“two-dimensional surface deviation [with] a difference between its greatest
elevation and its deepest valley of at least λ,” as recited in claims 1, 18,
and 32, or to implement “the non-rotationally symmetrical surface having a
deviation of at least 500 λ in relation to each rotationally symmetrical
surface at at least one point,” as recited in independent claim 21.
Based upon the findings above, on this record, we are persuaded of at
least one error in the Examiner’s reliance on the cited prior art to teach or
suggest the disputed limitation of independent claims 1, 18, 21, and 32, such
that we find error in the Examiner’s resulting legal conclusion of
obviousness.
Accordingly, we do not sustain the Examiner’s obviousness rejection
of independent claims 1, 18, 21, and 32, and dependent claims 2–12, 14–18
which depend from independent claim 1.
3. § 103 Rejection R3 of Claims 19 and 20
Issue 3
Appellant argues (Appeal Br. 7–13; Reply Br. 2) the Examiner’s
rejection of independent claims 19 and 20 under 35 U.S.C. § 103(a) as being
obvious over Chan is in error. These contentions present us with the
following issue:
Did the Examiner err in finding the cited prior art teaches or suggests
“[a]n imaging optical system” that includes “optical elements configured to
guide electromagnetic radiation with a wavelength λ in an imaging beam
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path to image an object field from an object plane into an image plane,
wherein,” inter alia, “at least two of the optical elements have a non mirror-
symmetrical surface which deviates at at least one point from each mirror-
symmetrical surface by at least λ/10,” as recited in claim 19? (emphasis
added).
Analysis
Similar to Issue 2 concerning claim 1, supra, the Examiner finds
“Chan does not specifically disclose the non mirror-symmetrical surface
deviates at at least one point from each mirror-symmetrical surface by at
least λ/10. However, Chan further discloses in paragraph [0079] that: ‘The
parameters for the freeform mirror equation can be determined using
commercially-available optical design software.’” Final Act. 15. Again, the
Examiner relies upon the holding in Aller for the proposition that “where the
general conditions of a claim are disclosed in the prior art, discovering the
optimum or workable ranges involves only routine skill in the art.” Id.
(citing In re Aller, 105 USPQ 233 (C.C.P.A. 1955)). The Examiner further
finds “[t]he benefits of discovering the optimum or workable ranges for
Chan’s disclosed deviation from mirror symmetry include providing
additional degrees of freedom that commercially-available optical design
software can use to improve correction of aberrations in the imaging optical
system.” Id.
For the same reasons as discussed above with respect to Issue 2, we
do not sustain the Examiner’s Rejection R3 of claims 19 and 20.
In particular, we are not persuaded because the Examiner has not, by a
preponderance of evidence, demonstrated that adjusting various mirror
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parameters in Chan, even by utilizing commercially-available optical design
software, would have led an ordinarily skilled artisan to the claimed
invention, nor has the Examiner established by evidence or analysis that any
of the mirror parameters available to Chan are result-effective variables that
would have led an ordinarily skilled artisan to a decision to implement “at
least two of the optical elements hav[ing] a non mirror-symmetrical surface
which deviates at at least one point from each mirror-symmetrical surface by
at least λ/10,” as recited in claim 19, or to implement “the non mirror-
symmetrical surface deviating by at least 10 λ from each mirror symmetrical
surface at at least one point” as recited in independent claim 20.
Based upon the findings above, on this record, we are persuaded of at
least one error in the Examiner’s reliance on the cited prior art to teach or
suggest the disputed limitations of independent claims 19 and 20, such that
we find error in the Examiner’s resulting legal conclusion of obviousness.
Accordingly, we do not sustain the Examiner’s obviousness Rejection
R3 of independent claims 19 and 20.
CONCLUSIONS
(1) The Examiner did not err with respect to anticipation Rejection
R1 of claim 20 under 35 U.S.C. § 102(e), and we sustain the rejection.
(2) The Examiner erred with respect to obviousness Rejections R2
and R3 of claims 1–12, 14–21, and 30–32 under 35 U.S.C. § 103(a) over the
cited prior art of record, and we do not sustain the rejections.

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DECISION SUMMARY
Claims
Rejected
35 U.S.C.
§
Basis /
References Affirmed Reversed
20 102(e) Anticipation Mann 20
1–12, 14–18,
21, 30–32 103(a)
Obviousness
Kugler
1–12, 14–18,
21, 30–32
19, 20 103(a) Obviousness Chan 19, 20
Overall
Outcome 20
1–12, 14–19,
21, 30–32
FINALITY AND RESPONSE
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(1)(iv). See 37
C.F.R. § 41.50(f).
AFFIRMED-IN-PART