Trials@uspto.gov
`571-272-7822
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`Paper 10
`Entered: December 16, 2013
`
`
`
`
`
`UNITED STATES PATENT AND TRADEMARK OFFICE
`____________
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`____________
`
`
`CARL ZEISS SMT GMBH
`Petitioner
`
`v.
`
`NIKON CORPORATION
`Patent Owner
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`
`Before HOWARD B. BLANKENSHIP, SALLY C. MEDLEY, and
`MATTHEW R. CLEMENTS, Administrative Patent Judges.
`
`
`CLEMENTS, Administrative Patent Judge.
`
`
`
`
`
`
`
`DECISION
`Institution of Inter Partes Review
`37 C.F.R. § 42.108
`
`
`
`
`571-272-7822
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`Paper 10
`Entered: December 16, 2013
`
`
`
`
`
`UNITED STATES PATENT AND TRADEMARK OFFICE
`____________
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`____________
`
`
`CARL ZEISS SMT GMBH
`Petitioner
`
`v.
`
`NIKON CORPORATION
`Patent Owner
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`
`Before HOWARD B. BLANKENSHIP, SALLY C. MEDLEY, and
`MATTHEW R. CLEMENTS, Administrative Patent Judges.
`
`
`CLEMENTS, Administrative Patent Judge.
`
`
`
`
`
`
`
`DECISION
`Institution of Inter Partes Review
`37 C.F.R. § 42.108
`
`
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`
`I.
`
`INTRODUCTION
`
`Carl Zeiss SMT GmbH (“Carl Zeiss”) filed a petition requesting inter partes
`
`review of claims 1–3, 8–12, 16–20, 23–26, and 29–33 of U.S. Patent No.
`
`7,348,575 B2 (Ex. 1001, “the ’575 patent”). Paper 3 (“Pet.”). The patent owner,
`
`Nikon Corporation (“Nikon”), did not file a preliminary response. We have
`
`jurisdiction under 35 U.S.C. § 314.
`
`The standard for instituting an inter partes review is set forth in 35 U.S.C.
`
`§ 314(a), which provides as follows:
`
`THRESHOLD.—The Director may not authorize an inter partes
`review to be instituted unless the Director determines that the
`information presented in the petition filed under section 311 and any
`response filed under section 313 shows that there is a reasonable
`likelihood that the petitioner would prevail with respect to at least 1 of
`the claims challenged in the petition.
`
`Upon consideration of the petition, we determine that the information
`
`presented by Carl Zeiss establishes that there is a reasonable likelihood that Carl
`
`Zeiss would prevail in showing unpatentability of claims 1–3, 8–12, 16–20, 23–26,
`
`and 29–33 of the ’575 patent. Accordingly, pursuant to 35 U.S.C. § 314, we
`
`institute an inter partes review for claims 1–3, 8–12, 16–20, 23–26, and 29–33 of
`
`the ’575 patent.
`
`A. Related Proceedings
`
`Seven applications claim benefit under 35 U.S.C. § 120 to the application
`
`that issued as the ’575 patent: 11/513,160 (pending); 11/583,934 (issued as U.S.
`
`Patent No. 7,309,870 ); 11/583,916 (issued as U.S. Patent No. 7,312,463 );
`
`11/882,208 (abandoned); 12/379,415 (pending); 12/884,332 (abandoned); and
`
`2
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`13/275,760 (pending). Pet. 1-2. United States Patent No. 7,309,870 has been the
`
`subject of four interference proceedings. Id. Carl Zeiss also has filed another
`
`petition for inter partes review of claims 55–67 of the ’575 patent: IPR2013-
`
`00363. In addition to these identified related proceedings, Nikon indicates that
`
`U.S. Patent Application No. 13/889,780 may affect, or may be affected by, a
`
`decision in this inter partes review. Paper 8.
`
`B. The ’575 Patent
`
`The subject matter of the ’575 patent relates to a catadioptric projection
`
`optical system, exposure apparatus, and exposure method and, more particularly, to
`
`a high-resolution catadioptric projection optical system suitable for use in
`
`production of semiconductor devices and liquid-crystal display devices by
`
`photolithography. Ex. 1001, col. 1, ll. 18-23. In the production of semiconductor
`
`devices, photolithography uses a projection exposure apparatus to project “an
`
`image of a mask (or reticle) through a projection optical system onto a wafer (or a
`
`glass plate or the like) coated with a photoresist or the like.” Ex. 1001, col. 1,
`
`ll. 27–32. As the dimensions of semiconductor devices shrink, the projection
`
`optical system of the projection exposure apparatus requires greater resolving
`
`power (resolution). Ex. 1001, col. 1, ll. 32–36. In order to satisfy the requirements
`
`for the resolving power of the projection optical system, it is necessary to shorten
`
`the wavelength of illumination light (exposure light) and to increase the image-side
`
`numerical aperture of the projection optical system. Ex. 1001, col. 1, ll. 37–41. It
`
`was known to increase the numerical aperture by putting a medium with a high
`
`refractive index, like a liquid, in the optical path between the projection optical
`
`3
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`system and the image plane. Ex. 1001, col. 1, ll. 55–58. However, there were
`
`known disadvantages to this approach. Ex. 1001, col. 1, ll. 59–67.
`
`The ’575 patent discloses systems and methods to provide a relatively
`
`compact projection optical system that is “corrected for various aberrations, such
`
`as chromatic aberration and curvature of field, and is capable of securing a large
`
`effective image-side numerical aperture while suppressing the reflection loss on
`
`optical surfaces.” Ex. 1001, col. 2, ll. 3–9. A medium having a refractive index
`
`larger than 1.1, such as deionized water, is interposed in the optical path between
`
`the boundary lens and the image plane, thereby increasing the image-side
`
`numerical aperture. Ex. 1001, col. 5, ll. 9–21. The projection optical system is
`
`catadioptric, comprising at least two reflecting mirrors, in which every transmitting
`
`member and every reflecting member with a refracting power are arranged along a
`
`single optical axis and in which the projection optical system has an effective
`
`imaging area that does not include the optical axis. Ex. 1001, col. 5, ll. 39–45. By
`
`arranging the transmitting members and the reflecting members along a single axis,
`
`the system is easier to produce than a system wherein the optical members are
`
`arranged along multiple optical axes. Ex. 1001, col. 5, ll. 52–59.
`
`C. Exemplary Claim
`
`Claim 1 is representative and is reproduced below:
`
`1. A catadiopt[ri]c projection optical system, which forms a reduced
`image of a first surface on a second surface, comprising:
`
`at least two reflecting mirrors; and
`
`a boundary lens whose surface on the first surface side has a
`positive refractive power,
`
`4
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`
`wherein where a refractive index of an atmosphere in an optical
`path of the projection optical system is 1, an optical path between the
`boundary lens and the second surface is filled with a medium having a
`refractive index la[r]ger than 1.1,
`
`wherein every transmitting member and every reflecting
`member with a refractive power constituting the projection optical
`system are arranged along a single optical axis; and
`
`the projection optical system having an effective imaging area
`of a predetermined shape not including said optical axis.
`
`D. Prior Art Relied Upon
`
`Carl Zeiss relies on the following prior art references, as well as the
`
`declaration of Richard C. Juergens (Ex. 1016):
`
`Suwa
`
`US 5,825,043
`
`Oct. 20, 1998 Ex. 1009
`
`Terasawa US 2002/0024741 A1
`
`Feb. 28, 2002 Ex. 1008
`
`Fukami1 WO 99/49504
`
`Takahashi2 WO 02/035273
`
`Sept. 30, 1999 Ex. 1012
`
`May 2, 2002
`
`Ex. 1007
`
`Suenaga
`
`EP 1 069 448 B1
`
`Mar. 19, 2003 Ex. 1027
`
`
`
`1 Fukami is a Japanese language document. Ex. 1012. Unless indicated otherwise,
`all subsequent references to Fukami in this decision will refer to its certified
`English language translation. Ex. 1015.
`2 Takahashi is a Japanese language document. Ex. 1007. Unless indicated
`otherwise, all subsequent references to Takahashi in this decision will refer to its
`publication in English by the European Patent Office as EP 1 336 887 A1. Ex.
`1014. Patent Owner admitted that EP 1 336 887 A1 is the English publication of
`WO 02/035273. Ex. 1026 at 35-36 (material facts 130 and 131, Admitted).
`5
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`
`Asai
`
`Satori Asai et al., “Resolution
`Limit for Optical Lithography
`Using Polarized Light
`Illumination,” 32 Jpn. J. Appl.
`Phys. 5863–5866 (1993)
`
`Switkes M. Switkes and M. Rothschild,
`“Resolution Enhancement of
`157 nm Lithography by Liquid
`Immersion,” 4691 Proc. SPIE
`pp. 460–465 (2002)
`
`Ulrich
`
`Willi Ulrich et al., “The
`Development of Dioptric
`Projection Lenses for DUV
`Lithography,” 4832 Proc. SPIE
`pp. 158–169 (2002)
`
`Dec. 1993
`
`Ex. 1013
`
`2002
`
`Ex. 1010
`
`2002
`
`Ex. 1011
`
`Carl Zeiss refers to Suwa, Switkes, Ulrich, and Fukami collectively as the
`
`“Immersion References.” Pet. 4.
`
`E. The Alleged Grounds of Unpatentability
`
`Carl Zeiss alleges that the challenged claims are unpatentable based upon the
`
`following grounds:
`
`Reference[s]
`
`Takahashi and the
`Immersion References
`Terasawa and the
`Immersion References
`Takahashi, the
`Immersion References,
`and Suenaga
`
`Basis
`
`§ 103
`
`§ 103
`
`§ 103
`
`Claims challenged
`
`1–3, 10, 16–20, 24, 25, 29,
`31–33
`1–3, 8–12, 16–20, 23–26,
`29, 31–33
`26
`
`6
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`
`Takahashi, the
`Immersion References,
`and Asai
`Terasawa, the Immersion
`References, and Asai
`
`§ 103
`
`§ 103
`
`30
`
`30
`
`F. Effective Filing Date
`
`The ’575 patent is a continuation-in-part of application No.
`
`PCT/JP2004/006417, which was filed on May 6, 2004. Ex. 1001, cover page. All
`
`of the patents and publications that Carl Zeiss relies upon are dated more than one
`
`year before May 6, 2004. Thus, based on the record before us, all of the patents
`
`and publications that Petitioner relies upon are prior art.
`
`II. ANALYSIS
`
`A. Claim Construction
`
`In an inter partes review, claim terms in an unexpired patent are interpreted
`
`according to their broadest reasonable construction in light of the specification of
`
`the patent in which they appear. 37 C.F.R. § 42.100(b); Office Patent Trial
`
`Practice Guide, 77 Fed. Reg. 48756, 48766 (Aug. 14, 2012). Also, claim terms are
`
`given their ordinary and customary meaning, as would be understood by one of
`
`ordinary skill in the art in the context of the entire disclosure. In re Translogic
`
`Tech., Inc., 504 F.3d 1249, 1257 (Fed. Cir. 2007).
`
`Carl Zeiss contends that the words in the challenged claims generally should
`
`have their plain meaning. Pet. 13. However, Carl Zeiss provides its own
`
`interpretations of five terms—“boundary lens,” “a refractive index . . . is 1,”
`
`“effective imaging area,” “every effective imaging area,” and “the second imaging
`
`7
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`optical system.” Pet. 13–15. For this decision, we construe each of these claim
`
`terms in turn.
`
`1. “boundary lens” (claim 1)
`
`Carl Zeiss contends that “when an immersion liquid is introduced between
`
`the last lens element of the projection optical system and the wafer (as in limitation
`
`[1d]), the last lens element becomes a ‘boundary lens.’” Pet. 14. This is consistent
`
`with the use of the term “boundary lens” in the ’575 patent. See, e.g., Ex. 1001,
`
`col. 20, ll. 45-49 (“FIG. 3 is an illustration schematically showing a configuration
`
`between the boundary lens and the wafer in the first example of the present
`
`embodiment.”), Figs. 3, 4, 5, 7 (each depicting boundary lens Lb as the last lens
`
`element). On this record, we determine that the broadest reasonable interpretation
`
`for “boundary lens” is “the last lens element of the projection optical system.”
`
`2. “a refractive index . . . is 1” (claim 1)
`
`Carl Zeiss contends that “a refractive index . . . is 1” should be interpreted as
`
`“equal to 1 to within at least the first decimal place.” Pet. 14. We understand
`
`“equal to 1 within at least the first decimal place” to mean that the refractive index
`
`may be any number ranging between 1.0 and 1.01. Carl Zeiss’s proposal is
`
`consistent with the ’575 patent’s use of the first decimal place later in claim 1
`
`(“having a refractive index la[r]ger than 1.1”). Specifically, the use of the first
`
`decimal place—i.e., “1.1”—elsewhere in the claim implies that the recited “1”
`
`means “1.0;” otherwise the first decimal place—i.e., the first digit to the right of
`
`the decimal—would have been specified there as well. Carl Zeiss’s proposal is
`
`also consistent with the examples in the specification of the atmosphere in the
`
`projection optical system being an inert gas, such as helium or nitrogen, which has
`
`8
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`a refractive index close to, but not exactly, equal to 1. Ex. 1001, col. 20, ll. 24-44;
`
`see also Ex. 1016 ¶¶ 86-92. On this record, we determine that “a refractive index
`
`. . . is 1” means “a refractive index . . . equal to 1 within at least the first decimal
`
`place, e.g., any number ranging between 1.0 and 1.01”
`
`3. “effective imaging area” (claim 1)
`
`Carl Zeiss contends that “effective imaging area” should be interpreted to
`
`mean the same thing as “effective exposure area” and “effective exposure region
`
`ER.” Pet. 15. The ’575 patent states that “FIG. 2 is an illustration showing a
`
`positional relation between the optical axis and an effective exposure area of
`
`arcuate shape,” and that “an effective exposure region (effective imaging area) ER
`
`is set in an arcuate shape . . . .” Ex. 1001, col. 19, l. 65 to col. 20, l. 9. Thus, based
`
`on our review of the specification of the ’575 Patent, we agree that these terms are
`
`used interchangeably.
`
`4. “every effective imaging area” (claim 18)
`
`Carl Zeiss contends that “every effective imaging area” should be
`
`interpreted to mean “the effective imaging area formed on the second surface as
`
`the final image, as well as effective imaging areas corresponding to any
`
`intermediate images.” Pet. 15. The term “every effective imaging area” is not
`
`used in the ’575 patent outside of claim 18. As support for its position, Carl Zeiss
`
`cites only to the Declaration of Richard C. Juergens. Id., citing Ex. 1016 ¶ 93. The
`
`’575 patent describes an “effective imaging area” and describes “intermediate
`
`images,” but does not describe “effective imaging areas corresponding to any
`
`intermediate images.” Specifically, the “effective imaging area” is the arcuate
`
`shape formed on a wafer, as depicted in Figure 2.
`
`9
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`
`
`
`Ex. 1001, Fig. 2, col. 19, l. 65 to col. 20, l. 23. In contrast, “intermediate images”
`
`are images of the reticle formed on various components of the first imaging optical
`
`system and second imaging optical system. See e.g. Ex. 1001, col. 21, ll. 56-67.
`
`Because the ’575 patent refers only to an area on a wafer as the “effective imaging
`
`area,” and never once refers to an intermediate image as having a corresponding
`
`effective imaging area, Carl Zeiss has not presented sufficient and credible
`
`evidence that patentee intended “every effective imaging area” to encompass
`
`“effective imaging areas corresponding to any intermediate images.” Based on our
`
`review of the Specification, “every effective imaging area” refers to all of the
`
`effective imaging areas of the claimed projection optical system, of which there is
`
`only one: the “effective imaging area” recited in claim 1. We, therefore, construe
`
`“every effective imaging area” as commensurate in scope with the “effective
`
`imaging area” recited in claim 1.
`
`10
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`
`5. “the second imaging optical system” (claim 25)
`
`Carl Zeiss contends that “the second imaging optical system” should be
`
`interpreted to mean the “second lens unit” recited in claim 10. Pet. 15–16. We
`
`disagree. Claim 25 recites “wherein the second imaging optical system is a
`
`dioptric system consisting of only a plurality of transmitting members.” Claim 25
`
`depends from claims 1 and 10. However, neither claim 1 nor claim 10 recites a
`
`“second imaging optical system.” The Specification of the ’575 patent is
`
`ambiguous. The ’575 patent does not describe only a “second imaging optical
`
`system” or only a “second lens unit” as “consisting of only a plurality of
`
`transmitting members.” All described embodiments of the “second lens unit”
`
`described in the ’575 patent “consist[] only of a plurality of transmitting
`
`members.” Ex. 1001, Figs. 5, 7, 9, 14, 15, 16. Some, but not all, embodiments of
`
`the “second imaging optical unit” are “dioptric systems consisting of only of a
`
`plurality of transmitting members.” See, e.g., Ex. 1001, Fig. 5 (second imaging
`
`optical system G2 consisting only of lenses), Fig. 7 (second imaging optical system
`
`G2 consisting only of lenses), Fig. 14 (second imaging optical system G2
`
`consisting only of lenses), Fig. 15 (second imaging optical system G4 consisting
`
`only of lenses), Fig. 16 (second imaging optical system G6 consisting only of
`
`lenses). At least one embodiment of the “second imaging optical system” is not.
`
`Ex. 1001, Fig. 9 (second imaging optical system G2 including two reflecting
`
`mirrors M3 and M4).
`
`Claims 20, 21, 22, 23, 24, and 26 all depend, directly or indirectly, on claim
`
`19. Claim 19 recites a “first imaging optical system” and a “second imaging
`
`optical system.” Claim 20 depends from claim 19 and defines further limitations
`
`11
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`on the “first imaging optical system” recited in claim 19. In this context, claim
`
`25’s recitation of “[t]he projection optical system according to claim 10” appears
`
`to be a typographical error in which “10” should be “19” or “20.” On this record,
`
`we construe “the second imaging optical system” to mean the “second imaging
`
`optical system” recited in claim 19.
`
`B. Claims 1-3, 8-12, 16-20, 23-26, 29, and 31-33 – Obvious over Terasawa and
`the Immersion References
`
`Carl Zeiss alleges that claims 1-3, 8-12, 16-20, 23-26, 29, and 31-33 are
`
`unpatentable under 35 U.S.C. § 103(a) over Terasawa and the Immersion
`
`References. Pet. 31–50, 55–56. In light of the arguments and evidence, Carl Zeiss
`
`has established a reasonable likelihood that 1–3, 8–12, 16–20, 23–26, 29, and 31–
`
`33 are unpatentable as obvious over Terasawa and the Immersion References.
`
`Terasawa describes a projection optical system and a projection exposure
`
`apparatus for projecting a pattern of a mask onto a substrate through the projection
`
`optical system. Ex. 1008 ¶ 0001. Figure 1 of Terasawa, reproduced below, depicts
`
`a catadioptric projection optical system including a first imaging system G1 and a
`
`second imaging system G2 for projecting an image of reticle 101 illuminated with
`
`illumination system (not shown) onto wafer 102:
`
`
`
`12
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
` Figure 1 of Terasawa depicts a catadioptric projection optical system. Ex. 1008 ¶¶
`
`55, 102, 103. “The first imaging optical system G1 comprises, in order from the
`
`object side, at least a first mirror M1, having a refracting element L1, [and] a
`
`second mirror M2.” Ex. 1008 ¶ 103. Light from reticle 101 is imaged by first
`
`imaging optical system G1, whereby intermediate image Io is formed. Id.
`
`Intermediate image Io, as imaged by first imaging optical system G1, is then
`
`imaged on wafer 102 by second imaging optical system G2, comprising a
`
`refracting element, at a predetermined magnification. Id. In the structure
`
`described above, the optical system of the first embodiment has one optical axis
`
`103, and produces a multiple-number imaging optical system wherein abaxial
`
`light, without light interception of a pupil, is imaged. Id. With the structure
`
`described above, light can be directed to the second imaging optical system
`
`without a void in a pupil and without bend of the optical axis. Ex. 1008 ¶ 105.
`
`The region of the object plane from which the light reaches the image plane, and
`
`which is attributable to the imaging, is a semi-arcuate zone. Ex. 1008, FIG. 3 ¶
`
`117.
`
`Carl Zeiss acknowledges that Terasawa does not disclose expressly “an
`
`optical path between the boundary lens and the second surface is filled with a
`
`medium having a refracting index larger than 1.1,” as recited in claim 1. Pet. 34,
`
`55. For that limitation, Carl Zeiss cites to the Immersion References (Suwa,
`
`Switkes, Ulrich, and Fukami). Pet. 36, 44–50, 55–56.
`
`Suwa describes “a means for improving the resolution without largely
`
`increasing the numerical aperture of the projection optical system,” in which “an
`
`immersion projection method may be used in which the space between the wafer
`
`13
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`and the projection optical system is filled with a liquid.” Ex. 1009, col. 3, ll. 18–
`
`23. Specifically:
`
`In this immersion projection method, the air space between the wafer
`and the optical element constituting the projection optical system on
`the projection end side (image plane side) is filled with a liquid having
`a refractive index close to the refractive index of the photoresist layer,
`to increase the effective numerical aperture of the projection optical
`system seen from the wafer side, i.e. improving the resolution. This
`immersion projection method is expected to attain good imaging
`performance by selecting the liquid used.
`
`Ex. 1009, col. 3, ll. 24–33. Figure 9 of Suwa is reproduced below:
`
`Figure 9 of Suwa depicts a projection optical system (PL) with an immersion fluid
`
`(LQ). Ex. 1009, col. 23, ll. 59-65. Suwa discloses that the last lens element, LE1,
`
`is a “positive lens element [] having a flat lower surface Pe and a convex upper
`
`surface,” and “is fixed on the end of the projection lens system PL inside the lens
`
`
`
`14
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`barrel.” Ex. 1009, 23:9–11. Suwa also discloses that the projection optical system
`
`can be catadioptric. Ex. 1009, 20:13–21. Carl Zeiss acknowledges that Suwa does
`
`not disclose expressly that the liquid has a refractive index greater than 1.1, but
`
`contends that:
`
`[A person of ordinary skill in the art] would know that “a refractive
`index close to the refractive index of the photoresist” would be a
`refractive index greater than 1.1. For example, U.S. Patent No.
`4,346,164 (“Tabarelli”), to which the passage from Suwa cited above
`expressly refers, identifies the refractive index of the photoresist as
`1.6, and goes on to list nine immersion liquids with refractive indices
`between 1.5 and 1.66. (ZEISS 1016; ¶¶ 199-201; ZEISS 1025, 3:57-
`60, 5:36-50.)
`
`Pet. 45. We are persuaded by Carl Ziess’s reasoning.
`
`Switkes teaches that immersion lithography can be used to enhance
`
`resolution by increasing numerical aperture and also can be used to increase depth
`
`of focus. Ex. 1010, p.459 (“Immersion lithography is a technique which can
`
`enhance the resolution of projection lithography by permitting exposures with
`
`numerical aperture (NA) greater than one, the theoretical maximum for
`
`conventional ‘dry’ systems. . . . Liquid immersion also increases the wafer depth of
`
`focus, i.e. the tolerable error in the vertical position of the wafer, by the index of
`
`the immersion liquid compared to a dry system with the same numerical
`
`aperture.”) (footnotes omitted). Switkes describes several immersion liquids for
`
`use at 157nm and 193nm whose refractive indexes are greater than 1.2. Ex. 1010,
`
`p.461. Switkes describes how immersion can be used with “much of conventional
`
`designs.” Ex. 1010, p.461.
`
`15
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`
`Ulrich describes the application of immersion lithography to prior art “dry”
`
`designs to achieve increased numerical aperture. Ex. 1011, p.166–167. Ulrich
`
`expressly teaches that “immersion designs can be applied to other design concepts
`
`such as catadioptric designs with similar results.” Ex. 1011, p.167. Thus, Carl
`
`Zeiss contends that “Ulrich demonstrates that the level of ordinary skill in this art
`
`is high and how, at the time of the alleged invention, there was not only express
`
`teaching to modify prior art ‘dry’ catadioptric projection optical system to include
`
`the immersion limitation to thereby increase NA, but also the skill necessary to do
`
`so.” Pet. 48, citing Ex. 1016 ¶¶ 22–24, 77–81, 223–224.
`
`Fukami describes the use of liquid immersion to improve the resolution of
`
`conventional projection exposure apparatuses. Ex. 1015, 3, ll. 13-28.3 Fukami
`
`expressly describes the applicability of immersion techniques to a catadioptric
`
`optical projection system having two mirrors and a single optical axis. Ex. 1015,
`
`21, ll. 13–16 (“Furthermore, the projection optical system PL can be a dioptric,
`
`catoptric, or catadioptric system, for example an optical system which has a
`
`plurality of dioptric elements and two catoptric elements (at least one of which is a
`
`concave mirror) disposed on an optical axis extending straight without being bent .
`
`. . .”).
`
`We are persuaded by Carl Ziess’s reasoning that the Immersion References
`
`(Suwa, Switkes, Ulrich, and Fukami) collectively teach “an optical path between
`
`the boundary lens and the second surface is filled with a medium having a
`
`refracting index larger than 1.1,” as recited in claim 1.
`
`
`
`3 Pages numbers refer to the bottom number on the page.
`
`16
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`
`Finally, we are persuaded by Carl Zeiss’s reasoning that a person of ordinary
`
`skill in the art would have been motivated to modify Terasawa to include the
`
`immersion limitation in view of the Immersion References in order to “minimize
`
`field curvature, avoid a pupil obscuration, and produce simple single barrel
`
`structures.” Pet. 55; see also Pet. 51-54.
`
`For the foregoing reasons, Carl Zeiss has established a reasonable likelihood
`
`that it would prevail in showing that claims 1, 29, 32, and 33 are unpatentable as
`
`obvious over Terasawa and the Immersion References. We also are persuaded by
`
`Carl Zeiss’s arguments and evidence for the dependent claims proposed as
`
`unpatentable as obvious over Terasawa and the Immersion References.
`
`C. Claim 30 – Obvious over Terasawa, the Immersion References, and Asai
`
`Carl Zeiss alleges that claim 30 is unpatentable under 35 U.S.C. § 103(a)
`
`over Terasawa, the Immersion References, and Asai. Pet. 59–60. In light of the
`
`arguments and evidence, Carl Zeiss has established a reasonable likelihood that
`
`claim 30 is unpatentable as obvious over Terasawa, the Immersion References, and
`
`Asai.
`
`Claim 30 depends from claim 29. Claim 29 is directed to “[a]n exposure
`
`apparatus” comprising “the projection optical system according to claim 1.” As
`
`discussed above, Carl Zeiss has established a reasonable likelihood that Terasawa
`
`and the Immersion References render obvious the subject matter of claim 29.
`
`Carl Zeiss acknowledges that Terasawa does not disclose expressly
`
`“illumination light which is s-polarized with respect to the second surface,” as
`
`recited in claim 30. Pet. 58. Asai describes the use of S-polarized light in a high-
`
`17
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`numerical-aperture optical stepper system. Ex. 1013, Abstract. Specifically, Asai
`
`describes how “[l]ight polarized parallel to the plane of incidence, or P
`
`polarization, gives lower contrast images than light polarized perpendicular to the
`
`plane of incidence, or S polarization, because destructive interference between
`
`diffracted waves does not occur when the electric-field vectors are perpendicular.”
`
`Ex. 1013, p.5863 (footnotes omitted). Petitioner contends that:
`
`[I]t would have been obvious for a POSITA at the time of the alleged
`invention to provide s-polarized illumination at the wafer in the projection
`exposure apparatus of Terasawa to improve the contrast of the image at the
`wafer for the same reasons as those set forth supra in section IX with respect
`to Takahashi because Asai teaches the benefits of using such s-polarized
`illumination. (ZEISS 1016, ¶¶ 22-24, 77-81, 250-254, 256; ZEISS 1013, p.
`5863, abstract and intro.)
`
`Pet. 59–60. We are persuaded by Carl Ziess’s reasoning.
`
`For the foregoing reasons, Carl Zeiss has established a reasonable likelihood
`
`that it would prevail in showing that claim 30 is unpatentable as obvious over
`
`Terasawa, the Immersion References, and Asai.
`
`D. Other Grounds
`
`Carl Zeiss also asserts the following grounds of unpatentability:
`
`1. Claims 1–3, 10, 16–20, 24, 25, 29, and 31–33 are unpatentable under 35
`
`U.S.C. § 103 as obvious over Takahashi and the Immersion References;
`
`2. Claim 26 is unpatentable under 35 U.S.C. § 103 as obvious over Takahashi,
`
`the Immersion References, and Suenaga; and
`
`3. Claim 30 is unpatentable under 35 U.S.C. § 103 as obvious over Takahashi,
`
`the Immersion References, and Asai.
`
`18
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`Pet. 19–31, 50–54, and 56–59. Those asserted grounds are denied as redundant in
`
`light of the determination that there is a reasonable likelihood that the challenged
`
`claims are unpatentable based on the grounds of unpatentability on which we
`
`institute an inter partes review. See 37 C.F.R. § 42.108(a).
`
`III. CONCLUSION
`
`For the foregoing reasons, we determine that the information presented in
`
`the petition establishes that there is a reasonable likelihood that Carl Zeiss would
`
`prevail in establishing unpatentability of claims 1-3, 8-12, 16-20, 23-26, and 29-33
`
`of the ’575 patent.
`
`The Board has not made a final determination on the patentability of any
`
`challenged claim.
`
`Accordingly, it is
`
`IV. ORDER
`
`ORDERED that pursuant to 35 U.S.C. § 314, an inter partes review is
`
`hereby instituted as to claims 1-3, 8-12, 16-20, 23-26, and 29-33 of the ’575 patent
`
`on the following grounds:
`
`1. Claims 1-3, 8-12, 16-20, 23-26, 29, and 31-33 under 35 U.S.C. § 103 as
`
`obvious over Terasawa and the Immersion References;
`
`2. Claim 30 under 35 U.S.C. § 103 as obvious over Terasawa, the Immersion
`
`References, and Asai;
`
`
`
`FURTHER ORDERED that all other grounds raised in Carl Zeiss’s petition
`
`are denied because they are redundant in light of the grounds on the basis of which
`
`an inter partes review is being instituted;
`
`19
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`
`FURTHER ORDERED that pursuant to 35 U.S.C. § 314(d) and 37 C.F.R.
`
`§ 42.4, notice is hereby given of the institution of a trial on the grounds of
`
`unpatentability authorized above; the trial commences on the entry date of this
`
`decision; and
`
`FURTHER ORDERED that an initial conference call with the Board is
`
`scheduled for 1:30 PM Eastern Time on January 8, 2014; the parties are directed to
`
`the Office Patent Trial Practice Guide4 for guidance in preparing for the conference
`
`call, and should be prepared to discuss any proposed changes to the Scheduling
`
`Order entered concurrently herewith and any motion the parties anticipate filing
`
`during the trial.
`
`
`
`
`
`
`
`4 Office Patent Trial Practice Guide, 77 Fed. Reg. 48756, 48765-66 (Aug. 14,
`2012).
`
`20
`
`
`
`Case IPR2013-00362
`Patent 7,348,575 B2
`
`
`For PETITIONER:
`
`Marc M. Wefers, Esq.
`Chris C. Bowley, Esq.
`Fish & Richardson, P.C.
`wefers@fr.com
`bowley@fr.com
`
`
`
`For PATENT OWNER:
`
`John S. Kern, Esq.
`Robert C. Mattson, Esq.
`Oblon Spivak
`CPdocketKern@oblon.com
`CPdocketMattson@oblon.com
`
`
`21
`
`
Accessing this document will incur an additional charge of $.
After purchase, you can access this document again without charge.
Accept $ Charge
Still Working On It
This document is taking longer than usual to download. This can happen if we need to contact the court directly to obtain the document and their servers are running slowly.
Give it another minute or two to complete, and then try the refresh button.
A few More Minutes ... Still Working
It can take up to 5 minutes for us to download a document if the court servers are running slowly.
Thank you for your continued patience.
This document could not be displayed.
We could not find this document within its docket. Please go back to the docket page and check the link. If that does not work, go back to the docket and refresh it to pull the newest information.
Your account does not support viewing this document.
You need a Paid Account to view this document. Click here to change your account type.
Your account does not support viewing this document.
Set your membership
status to view this document.
With a Docket Alarm membership, you'll
get a whole lot more, including:
- Up-to-date information for this case.
- Email alerts whenever there is an update.
- Full text search for other cases.
- Get email alerts whenever a new case matches your search.
One Moment Please
The filing “” is large (MB) and is being downloaded.
Please refresh this page in a few minutes to see if the filing has been downloaded. The filing will also be emailed to you when the download completes.
Your document is on its way!
If you do not receive the document in five minutes, contact support at support@docketalarm.com.
Sealed Document
We are unable to display this document, it may be under a court ordered seal.
If you have proper credentials to access the file, you may proceed directly to the court's system using your government issued username and password.
Access Government Site
