`
`IN THE UNITED STATES PATENT AND TRADEMARK OFFICE
`
`In re Patent of: Yasuhiro Omura
`U.S. Patent No.: 7,348,575 Attorney Docket No.: 24984-0056IP2
`Issue Date: March 25, 2008
`Appl. Serial No.: 11/266,288
`Filing Date: Nov. 4, 2005
`Title:
`PROJECTION OPTICAL SYSTEM, EXPOSURE APPARATUS,
`AND EXPOSURE METHOD
`
`Mail Stop Patent Board
`Patent Trial and Appeal Board
`U.S. Patent and Trademark Office
`P.O. Box 1450
`Alexandria, VA 22313-1450
`
`
`
`PETITION FOR INTER PARTES REVIEW OF CLAIMS 55-67
`OF UNITED STATES PATENT NO. 7,348,575
`PURSUANT TO 35 U.S.C. §§ 311–319, 37 C.F.R. § 42
`
`
`
`
`
`
`
`

`

`
`
`TABLE OF CONTENTS
`
`I.
`MANDATORY NOTICES UNDER 37 C.F.R § 42.8 .................................... 1
`EVIDENCE ..................................................................................................... 2
`II.
`III. REQUIREMENTS FOR IPR UNDER 37 C.F.R. §§ 42.104 .......................... 2
`A. Grounds for Standing Under 37 C.F.R. § 42.104(a) ....................................... 3
`B. Identification of Challenge Under 37 C.F.R. § 42.104(b) ............................... 3
`IV. SUMMARY OF THE OMURA PATENT ..................................................... 6
`A. Technical Background ..................................................................................... 6
`B. The Alleged Invention of the Omura Patent .................................................. 10
`C. Claim Construction under 37 C.F.R. §§ 42.104(b)(3) ................................... 13
`D. Summary of the Prosecution History of the Omura Patent and Certain
`Related Applications ...................................................................................... 15
`THE PRIOR ART .......................................................................................... 16
`V.
`A. Prior Art Status of References ....................................................................... 16
`B. All of the Limitations of Independent Claim 55 are Disclosed in Mann ...... 19
`C. Claim Chart for Mann Rejections .................................................................. 23
`D. All of the Limitations of Independent Claim 55 are Disclosed in Takahashi
` ....................................................................................................................... 30
`E. Claim Chart for Takahashi Rejections .......................................................... 34
`F. All of the Limitations of Independent Claim 55 are Disclosed in Omura ‘387
` ....................................................................................................................... 38
`G. Claim Chart for Omura ‘387 Rejections ....................................................... 42
`H. Claim 61 is Unpatentable as Obvious over Takahashi in view of Suwa and
`Ulrich ............................................................................................................. 48
`I. Claim 61 is Unpatentable as Obvious over Omura ‘387 in view of Suwa and
`Ulrich ............................................................................................................. 53
`J. Claim 64 is Unpatentable as Obvious over Mann in view of Asai ............... 54
`K. Claim 64 is Unpatentable as Obvious over Takahashi in view of Asai ........ 56
`L. Claim 64 is Unpatentable as Obvious over Omura ‘387 in view of Asai ..... 57
`M. Claim 67 is Unpatentable as Obvious over Mann in view of Takahashi ...... 57
`N. Claim 67 is Unpatentable as Obvious over Omura ‘387 in view of Takahashi
` ....................................................................................................................... 58
`VI. CONCLUSION .............................................................................................. 59
`
`
`
`
`
`

`

`Petition for IPR of US 7,348,575
`Page 1
`Carl Zeiss SMT GmbH (“Petitioner” or “Zeiss”) petitions for Inter Partes
`
`Review (“IPR”) under 35 U.S.C. §§ 311–319 and 37 C.F.R. § 42 of claims 55-67
`
`of U.S. Patent No. 7,348,575 (“the Omura Patent”), and asserts that there is a rea-
`
`sonable likelihood that it will prevail with respect to at least one of the claims chal-
`
`lenged in this petition (hereinafter “the Petition”).
`
`I. MANDATORY NOTICES UNDER 37 C.F.R § 42.8
`
`Carl Zeiss SMT GmbH is the real party-in-interest. 37 C.F.R. § 42.8(b)(1)
`
`The following applications claim benefit under Section 120 to the applica-
`
`tion that issued as the Omura 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
`
`13/275,760 (pending). Among these, U.S. Patent No. 7,309,870 (“the Omura ’870
`
`Patent”), which issued from a continuation of the application that issued as the
`
`Omura Patent, has been the subject of four interferences between Zeiss and the as-
`
`signee of the Omura Patent, Nikon Corporation (“Nikon”), specifically Interfer-
`
`ence Nos. 105,678, 105,749, 105,753, and 105,834. (ZEISS 1101, cover page;
`
`ZEISS 1102, cover page.) Final judgment was entered against Nikon in each inter-
`
`ference and the involved claims of the Omura ’870 Patent were canceled. (ZEISS
`
`1103, p. 2; ZEISS 1104, p. 2; ZEISS 1105, p. 2; ZEISS 1106, p. 2.) In addition to
`
`the present Petition regarding the Omura Patent, Zeiss is filing a second IPR peti-
`
`
`
`

`

`Petition for IPR of US 7,348,575
`Page 2
`tion on the same date as the present Petition to address claims 1-3, 8-12, 16-20, 23-
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`26, and 29-33 of the Omura Patent. Zeiss is not aware of any other proceeding in-
`
`volving the Omura Patent. 37 C.F.R. § 42.8(b)(2).
`
`Petitioner provides the following designation of counsel. 37 C.F.R. §
`
`42.8(b)(3).
`
`LEAD COUNSEL
`Marc M. Wefers (Reg. No. 56,842)
`(wefers@fr.com)
`Fish & Richardson P.C.
`3200 RBC Plaza
`60 South Sixth Street
`Minneapolis, MN 55402
`T: 617-542-5070; F: 617-542-8906
`
`Please address all correspondence to the lead counsel at the address provided
`
`BACK-UP COUNSEL
`Chris C. Bowley (Reg. No. 55,016)
`(bowley@fr.com)
`Fish & Richardson P.C.
`3200 RBC Plaza
`60 South Sixth Street
`Minneapolis, MN 55402
`T: 212-765-5070; F: 212-258-2291
`
`above. Petitioner also consents to electronic service by email at: IPR24984-
`
`0056IP2@fr.com. 37 C.F.R. § 42.8(b)(4).
`
`We authorize the U.S. Patent and Trademark Office (the “Office”) to charge
`
`Deposit Account No. 06-1050 for the fee set in 37 C.F.R. § 42.15(a) for the Peti-
`
`tion, and further authorize payment for any additional fees to be charged to this
`
`Deposit Account.
`
`II. EVIDENCE
`Appendix 1 lists the exhibits relied on in the Petition.
`
`III. REQUIREMENTS FOR IPR UNDER 37 C.F.R. §§ 42.104
`
`
`
`

`

`Petition for IPR of US 7,348,575
`Page 3
`
`A. Grounds for Standing Under 37 C.F.R. § 42.104(a)
`Zeiss certifies that the Omura Patent is eligible for IPR and that Zeiss is not
`
`barred or estopped from requesting IPR.
`
`Identification of Challenge Under 37 C.F.R. § 42.104(b)
`
`B.
`Zeiss requests IPR of claims 55-67 of the Omura Patent (the “Challenged
`
`Claims”) based on the prior art and grounds set forth below, and requests that the
`
`Office finds each of these claims to be unpatentable.
`
`
`
`2.
`
`Prior Art Reference
`
`1. US Patent Application Publication No.
`US 2005/0036213 (“Mann”)
`JP Patent Application Publication No.
`JP 2003-114387 (“Omura ‘387 JP”)
`3. PCT Patent Publication No.
`WO 02/035273 (“Takahashi PCT”)
`4. Satori Asai et al., “Resolution Limit for Optical
`Lithography Using Polarized Light Illumina-
`tion,” Jpn. J. Appl. Phys. Vol. 32, pp. 5863-
`5866 (1993) (“Asai”)
`5. US Patent No. 5,825,043 (“Suwa”)
`
`Prior Art Date
`Filed Aug. 12, 2003
`(ZEISS 1110)
`Published Apr. 18, 2003
`(ZEISS 1111)
`Published May 2, 2002
`(ZEISS 1113)
`Published Dec. 1993
`(ZEISS 1114)
`
`Patented Oct. 20, 1998
`(ZEISS 1123)
`Published in 2002
`(ZEISS 1118)
`
`6. Willi Ulrich et al., “The Development of Diop-
`tric Projection Lenses for DUV Lithography,”
`Proc. SPIE Vol. 4832, pp. 158-169 (2002)
`(“Ulrich”)
`
`As explained in section V(A), infra, each of these references is prior art to
`
`the Omura Patent. Omura ‘387 JP is published in Japanese so a Certified English
`
`Translation (“Omura ‘387”) is provided as Exhibit No. 1112. (ZEISS 1112.)
`
`Takahashi PCT was published in Japanese and republished in English by the Euro-
`
`
`
`

`

`Petition for IPR of US 7,348,575
`Page 4
`pean Patent Office as EP 1336 887 A1 (“Takahashi”). (ZEISS 1114, Cover Page,
`
`(87); ZEISS 1128, material fact 131, admitted.) Accordingly, we refer to this Eng-
`
`lish publication of the Takahashi PCT when citing to Takahashi.
`
`An explanation of how the Challenged Claims are unpatentable under the
`
`statutory grounds is identified below, including the identification of where each el-
`
`ement is found in the prior art patents or publications and the relevance of the prior
`
`art references are provided in the form of detailed claim charts. Additional expla-
`
`nation and support for each ground of rejection is set forth in the Declaration of
`
`Richard C. Juergens. (ZEISS 1116.)
`
`Claim 55, the only independent claim being challenged, is anticipated by
`
`each of Mann, Takahashi, and Omura ‘387. Moreover, each of the dependent
`
`claims 56-67 are anticipated by one or more of these prior art references or obvious
`
`in view of these references in combination with Asai, Suwa, Ulrich and/or
`
`Takahashi. Ten separate grounds for invalidating various subsets of the Challenged
`
`Claims are summarized in the table below.
`
`Mann, Takahashi, and Omura ‘387 are not redundant. Mann has a later filing
`
`date than Takahashi and Omura ‘387 and is prior art under a different section of 35
`
`U.S.C. § 102 than Takahashi and Omura ‘387. Furthermore, each of these refer-
`
`ences anticipates a different subset of the Challenged Claims relative to the others.
`
`For example, Mann anticipates certain claims (e.g., claim 61, requiring “a medium
`
`
`
`

`

`Petition for IPR of US 7,348,575
`Page 5
`having a refractive index lager [sic] than 1.1 is interposed in an optical path be-
`
`tween the lens nearest to the second surface, and the second surface”), while
`
`Takahashi and Omura ‘387 do not. Furthermore, Takahashi provides disclosure
`
`relevant to certain claims that is not expressly provided by Mann or Omura ‘387
`
`(e.g., “developing the exposed photosensitive substrate”). On the other hand, Omu-
`
`ra ‘387 provides additional disclosure that is relevant to certain other dependent
`
`claims (e.g., requiring a third reflecting mirror that “bend[s] the light into a direc-
`
`tion toward the optical axis.”) Finally, because Zeiss cannot know what rebuttal
`
`arguments Nikon will make, we respectfully submit that using three primary refer-
`
`ences is not contrary to securing “the just, speedy, and inexpensive resolution” of
`
`this proceeding required by 37 C.F.R. § 42.1(b).
`
`Suwa and Ulrich are being applied collectively in both of the proposed obvi-
`
`ousness rejections of claim 61. While each reference independently discloses the
`
`immersion limitation missing from Takahashi and Omura ‘387, they provide inter-
`
`related and complimentary teachings to collectively reinforce why it would have
`
`been obvious to modify a dry system to include the immersion limitation. For ex-
`
`ample, Suwa was previously raised by the Office (and not disputed by Nikon) to
`
`demonstrate the obviousness of the immersion limitation. Ulrich describes in
`
`greater detail how to achieve the benefits of immersion described in Suwa (to in-
`
`crease numerical aperture). Asai addresses dependent claim 64.
`
`
`
`
`
`

`

`Petition for IPR of US 7,348,575
`Page 6
`
`
`Ground
`
`Omura Patent
`Claims
`Ground 1 55-63 and 65-67
`Ground 2 64
`
`Ground 3 67
`
`Ground 4 55, 59-60, 62-63, and
`65-67
`Ground 5 61
`
`Ground 6 64
`
`Ground 7 55, 58-60, 62-63, and
`65-67
`Ground 8 61
`
`Ground 9 64
`
`Ground 10 67
`
`
`
`Basis for Rejection
`
`Anticipated under § 102(e) by Mann
`Obvious under § 103(a) over Mann in view
`of Asai
`Obvious under § 103(a) over Mann in view
`of Takahashi
`Anticipated under § 102(b) by Takahashi.
`
`Obvious under § 103(a) over Takahashi in
`view of Suwa and Ulrich
`Obvious under § 103(a) over Takahashi in
`view of Asai
`Anticipated under § 102(b) over Omura
`‘387
`Obvious under § 103(a) over Omura ‘387
`in view of Suwa and Ulrich
`Obvious under § 103(a) over Omura ‘387
`in view of Asai
`Obvious under § 103(a) over Omura ‘387
`in view of Takahashi
`
`IV. SUMMARY OF THE OMURA PATENT
`
`A. Technical Background
`The Omura Patent relates to catadioptric projection optical systems for use
`
`in projection exposure apparatus used in the production of semiconductor devices.
`
`(ZEISS 1101, 1:18-23.) During operation, a projection exposure apparatus projects
`
`an image of a reticle pattern onto a “photosensitive substrate,” such as a wafer
`
`coated with a photoresist. In this field, the terms “reticle” and “mask” are used in-
`
`terchangeably. Further processing of the exposed coating, such as developing the
`
`
`
`

`

`Petition for IPR of US 7,348,575
`Page 7
`exposed coating and depositing material over the developed coating or etching ma-
`
`terial beneath the developed coating, allows one to build up the tiny complex com-
`
`ponents forming integrated circuits. The projection exposure apparatus generally
`
`includes an illumination system to illuminate the reticle pattern with light, the pro-
`
`jection optical system to project an image of the illuminated reticle pattern onto the
`
`photosensitive substrate, and a substrate positioning system to position the photo-
`
`sensitive substrate relative to the image. (ZEISS 1116, ¶¶ 25-30; see e.g., ZEISS
`
`1114, [0033]-[0035], [0051]-[0054], [0239], [0240]; ZEISS 1101, 1:29-30, 6:23,
`
`17:14.)
`
`A projection optical system typically includes multiple imaging elements.
`
`Each imaging element can be a “transmitting member,” such as a lens, or a “re-
`
`flecting member,” such as a curved mirror. Each imaging optical element bends
`
`lights rays to thereby focus or defocus light to a degree measured by its “power”
`
`(also referred to as “optical power,” “refracting power,” or “refractive power”).
`
`Each surface of a lens bends light rays based on its curvature and the refractive in-
`
`dex of the lens relative to the lower refractive index of the surrounding medium
`
`(e.g., air or water). (ZEISS 1116, ¶¶ 31, 39-48; see also ZEISS 1117.) For exam-
`
`ple, a convex lens surface will have positive power and focus light, whereas a con-
`
`cave lens surface will have negative power and defocus light. A mirror having a
`
`convex surface defocuses light it reflects and therefore has negative power, where-
`
`
`
`

`

`Petition for IPR of US 7,348,575
`Page 8
`as a mirror having a concave surface focuses light it reflects and therefore has posi-
`
`tive power. The power of a collection of imaging elements is determined by the
`
`degree to which the collection of elements as a whole focuses or defocuses light.
`
`(ZEISS 1116, ¶¶ 43-52.)
`
`A projection optical system whose imaging elements are all lenses is a “di-
`
`optric” optical system. A projection optical system whose imaging elements are all
`
`mirrors is a “catoptric” optical system. A projection optical system whose imaging
`
`elements include at least one lens and at least one mirror is a “catadioptric” optical
`
`system. Accordingly, a “catadioptric projection optical system” is a projection op-
`
`tical system whose imaging elements include at least one lens and at least one mir-
`
`ror. (ZEISS 1116, ¶¶ 61-62; see also ZEISS 1118, pp. 19-23.)
`
`The way a projection optical system projects an image from a first surface to
`
`a second surface can be depicted by tracing the paths of light rays emerging from
`
`the first surface through the optical elements that comprise the projection optical
`
`system onto the second surface. Specifically, multiple light rays emerging from
`
`each of multiple points on the first surface (defining the “object”) are recombined
`
`at each of corresponding points on the second surface (defining the “image”). In
`
`addition to the final image, a projection optical system can also include one or
`
`more intermediate images, which are intermediate locations between the first and
`
`second surfaces where multiple light rays emerging from each of multiple points
`
`
`
`

`

`Petition for IPR of US 7,348,575
`Page 9
`on the first surface (defining the “object”) are recombined at each of corresponding
`
`points. FIGS. 5, 7, 9, 10, and 14-16 in the Omura Patent are examples of such ray
`
`diagrams, with FIGS. 5, 7, 9, and 10 having one intermediate image and FIGS. 14-
`
`16 having two intermediate images. (ZEISS 1116, ¶¶ 32-38.)
`
`The surface of each imaging element in the projection optical system typi-
`
`cally corresponds to a mathematical surface that is rotationally symmetric about an
`
`axis. This axis defines the “optical axis” for the optical surface. The optical axis for
`
`an optical system comprising multiple surfaces is defined by the sequence of opti-
`
`cal axes for the respective surfaces. In many cases, the optical axes for all of the
`
`surfaces that define the optical system are the same. This is the case for all of the
`
`embodiments of the Omura Patent (i.e., the embodiments of FIGS. 5, 7, 9, 10, and
`
`14-16), each of which has a single optical axis AX. Such designs are sometimes
`
`referred to as “inline” designs. (ZEISS 1116, ¶¶ 56-58; ZEISS 1120; ZEISS 1101,
`
`16:3-17.)
`
`The shape and location of each imaging element surface in a projection opti-
`
`cal system is typically provided in the form of one or more tables, collectively
`
`called a “lens prescription.” (ZEISS 1116, ¶¶ 75, 76.) TABLE 1 in the Omura Pa-
`
`tent, for example, gives the lens prescription for the projection optical system
`
`shown in FIG. 5. (ZEISS 1101, 23:28-25:35.) A lens surface shape is typically de-
`
`fined by a radius of curvature. (ZEISS 1116, ¶ 45.) For aspherical lenses, the shape
`
`
`
`

`

`Petition for IPR of US 7,348,575
`Page 10
`of at least one surface is given by the radius of curvature and coefficients that char-
`
`acterize a deviation of the lens surface from the base sphere (See, e.g., ZEISS
`
`1101, 21:39-55; ZEISS 1116, ¶ 45.) Using optical design software, it is possible to
`
`trace rays through a projection optical system based on the lens prescription, and to
`
`determine a variety of characteristics of the system, such as the location of inter-
`
`mediate images in the system and the refractive power of groups of optical ele-
`
`ments. (ZEISS 1116, ¶¶ 75-79.)
`
`The resolving power of a projection optical system varies inversely with the
`
`size of smallest possible feature in the image produced by the projection optical
`
`system (“resolution”), which is expressed by the relationship kλ/NA, where λ is the
`
`operational wavelength of the system, NA refers to the image-side numerical aper-
`
`ture of the system (hereinafter “NA”), and k is a process co-efficient. NA equals
`
`n·sin θ, where n is a refractive index of a medium between the projection optical
`
`system and the image plane and θ is the maximum angle of incidence of the light
`
`rays forming the image on wafer. Accordingly, to improve resolution, one can re-
`
`duce the wavelength, λ, and/or increase NA. To increase NA, one can increase the
`
`maximum angle θ and/or increase the refractive index of the medium between the
`
`projection optical system and the image plane. (ZEISS 1116, ¶¶ 63-70; ZEISS
`
`1101, 1:37-48; ZEISS 1108, [0002]; ZEISS 1114, [0003].)
`
`B.
`
`The Alleged Invention of the Omura Patent
`
`
`
`

`

`Petition for IPR of US 7,348,575
`Page 11
`The Omura Patent is directed to a “high-resolution catadioptric projection
`
`optical system suitable for exposure apparatus used in production of semiconductor
`
`devices, liquid-crystal display devices, etc. by photolithography.” (ZEISS 1101,
`
`1:18-23.)
`
`The Omura Patent expressly discloses several “objects of the embodiment,”
`
`including achieving “a large numerical aperture, without increase in the scale of
`
`optical members forming a catadioptric projection optical system.” (ZEISS 1101,
`
`2:30-32.) Accordingly, in an aspect that relates specifically to the Challenged
`
`Claims, in order to achieve this object, the Omura Patent describes a catadioptric
`
`projection optical system for forming an image of a first surface on a second sur-
`
`face. (ZEISS 1101, 3:8-27; ZEISS 1116, ¶¶ 33, 61, 62.) This projection optical sys-
`
`tem has four units between the first surface and the second surface where, among
`
`other features, the second unit comprises “at least four mirrors,” the third unit “has
`
`a negative refracting power,” “an intermediate image is formed in the second unit,”
`
`and “an aperture stop is provided in the fourth unit.” (ZEISS 1101, 3:8-27.)
`
`The Omura Patent explains that, in general, the combination of mirrors and
`
`lenses in a catadioptric system can be used to correct for field curvature by satisfy-
`
`ing the Petzval condition. (ZEISS 1101, 5:45-51, 6:45-49.) In an aspect that relates
`
`specifically to the Challenged Claims, the Omura Patent explains that forming the
`
`intermediate image in the second unit achieves “the optical path separation be-
`
`
`
`

`

`Petition for IPR of US 7,348,575
`Page 12
`tween the beam toward the first surface and the beam toward the second surface,
`
`even in the case where the numerical apertures of the catadioptric projection opti-
`
`cal systems are increased.” (ZEISS 1101, 12:7-14.) Furthermore, according to the
`
`Omura Patent, “the total length of the catadioptric projection optical system can be
`
`decreased and the adjustment for satisfying the Petzval’s condition can be readily
`
`performed” by having a third unit that has negative optical power. (ZEISS 1101,
`
`12:14-18.)
`
`The detailed embodiment of FIG. 9 in the Omura Patent is exemplary of
`
`such features. (ZEISS 1116, ¶ 36.)
`
`Accordingly, independent claim 55 of the Omura patent, the only independ-
`
`ent claim subject to the Petition, recites (paragraph sub-headings added):
`
`[55a] A catadioptric projection optical system, which forms an image
`of a first surface on a second surface, comprising:
`[55b] a first unit disposed in an optical path between the first surface
`and the second surface and having a positive refractive power;
`[55c] a second unit disposed in an optical path between the first unit
`and the second surface and comprising at least four mirrors;
`[55d] a third unit disposed in an optical path between the second unit
`and the second surface, comprising at least two negative lenses, and
`having a negative refractive power; and
`[55e] a fourth unit disposed in an optical path between the third unit
`and the second surface, comprising at least three positive lenses, and
`having a positive refractive power,
`
`
`
`

`

`Petition for IPR of US 7,348,575
`Page 13
`[55f] wherein an intermediate image is formed in the second unit and
`wherein an aperture stop is provided in the fourth unit.
`
`C. Claim Construction under 37 C.F.R. §§ 42.104(b)(3)
`A claim subject to IPR is given its “broadest reasonable construction in light
`
`
`
`of the specification of the patent in which it appears.” 37 C.F.R. § 42.100(b). This
`
`means that the words of the claim are given their plain meaning unless that mean-
`
`ing is inconsistent with the specification. In re Zletz, 893 F.2d 319, 321 (Fed. Cir.
`
`1989). Unless otherwise addressed below, Zeiss submits that the words in the
`
`Challenged Claims take on this plain meaning, such as set forth in the Technical
`
`Background section, supra.
`
`Based on its express language, the catadioptric projection optical system of
`
`claim 55 of the Omura Patent includes a first, second, third, and fourth “unit.” For
`
`the purposes of the Petition, we give the term “unit” its plain meaning, which is a
`
`single, distinct part or object.1 The Omura Patent’s use of “unit” is consistent with
`
`this definition: the Omura Patent identifies single, distinct parts of catadioptric pro-
`
`jection objectives consisting of one or more consecutive lenses and/or mirrors as
`
`
`1 See, e.g., New World Dictionary of the American Language, Second College Edi-
`
`tion, Simon and Schuster (1980), which, among other definitions, defines “unit” as
`
`“a single, distinct part or object, esp. one used for a specific purpose [the lens unit
`
`of a camera].” (ZEISS 1021.)
`
`
`
`

`

`Petition for IPR of US 7,348,575
`Page 14
`corresponding to a unit. For example, the Omura Patent identifies distinct parts of
`
`catadioptric projection optical systems composed on one or more lenses as lens
`
`“units.” (See, e.g., ZEISS 1101, 30:11-31:1, identifying lens units G11, G21, G22,
`
`and G23 in FIG. 9; ZEISS 1116, ¶¶ 80-85.)
`
`Below we address certain issues in the dependent claims.
`
`Dependent claim 57 recites “the fourth reflecting mirror of a double pass
`
`fens” which appears to include two typographical error. For the purposes of the Pe-
`
`tition, we construe this phrase to mean “the fourth reflecting mirror or a double
`
`pass lens.” This is consistent with the specification of the Omura Patent. (ZEISS
`
`1101, 12:37-42.)
`
`Dependent claim 58 and dependent claim 59 each depend from claim 55 and
`
`recite “the third reflecting mirror,” but no third reflecting mirror is recited in claim
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`55. For the purposes of the Petition, we construe “the third reflecting mirror” in
`
`claims 58 and 59 to refer to a third of the “at least four mirrors” in the “second
`
`unit” recited in claim 55. (ZEISS 1116, ¶¶ 84, 87.)
`
`Dependent claim 62 recites “wherein an optical axis of every optical element
`
`with a predetermined refractive power in the catadioptric projection optical system
`
`is arranged substantially on a single straight line, and wherein a region of an image
`
`formed on the second surface by the catadioptric projection optical system is an
`
`off-axis region not including the optical axis.” It is unclear which of the optical ax-
`
`
`
`

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`Petition for IPR of US 7,348,575
`Page 15
`es is not included by the region of the image formed on the second surface. How-
`
`ever, for the purposes of the Petition, we interpret this to refer to any of the optical
`
`axes because the claim requires that they are all “arranged substantially on a single
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`straight line” – i.e., they are coaxial. (ZEISS 1116, ¶¶ 56-58, 91.) This is consistent
`
`with the specification of the Omura Patent. (See, e.g., ZEISS 1101, 31:19-25, FIG.
`
`9.) Accordingly, we further interpret the phrase “wherein a region of an image
`
`formed on the second surface by the catadioptric projection optical system is an
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`off-axis region not including the optical axis,” to require that the portion of the ret-
`
`icle imaged on the wafer is offset from the single straight line. (ZEISS 1116, ¶¶ 56-
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`60, 91.) This, too, is consistent with the specification of the Omura Patent. (See,
`
`e.g., ZEISS 1101, 20:7-8 and 14-23, FIG. 11.)
`
`D.
`
`Summary of the Prosecution History of the Omura Patent
`and Certain Related Applications
`
`The Omura Patent was issued after a first action allowance. (ZEISS 1122,
`
`Notice of Allowance mailed 10/29/2007.) Mann, Takahashi, and Omura ‘387 were
`
`each before the Examiner, but there was no substantive discussion of any of the
`
`references during prosecution. (ZEISS 1122, pp. 2, 6-9.)
`
`As explained in detailed infra, each of Mann, Takahashi, and Omura ‘387
`
`clearly anticipate independent claim 55. Specifically, they each disclose a cata-
`
`dioptric projection objective system having four units as recited by claim 55, where
`
`an intermediate image is formed in the second unit and an aperture stop is provided
`
`
`
`

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`Petition for IPR of US 7,348,575
`Page 16
`in the fourth unit. The specific requirements of claim 55 for each of the four units
`
`can be readily ascertained from the figures of the prior art projection optical sys-
`
`tems, the accompanying descriptions, and the lens prescriptions.
`
`In the Examiner’s statement for reasons for the allowance, the Examiner did
`
`not explain which feature or combination of features recited in claim 55 the Exam-
`
`iner believed patentably distinguished the prior art. (ZEISS 1122, pp. 7-8.) Instead,
`
`the Examiner stated that the “prior art fails to disclose or make obvious, in combi-
`
`nation with other recited features of the claims’ limitations, a relatively compact
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`high resolution catadioptric projection optical system” that includes a variety of
`
`features not recited in claim 55. (ZEISS 1122, pp. 7-8.)
`
`V. THE PRIOR ART
`A.
`Prior Art Status of References
`
`1.
`Takahashi, Omura ‘387, Suwa, Ulrich and Asai are
`Prior Art under 35 U.S.C. § 102(b)
`
`The application which issued as the Omura Patent was filed on November 4,
`
`2005 as a continuation-in-part of PCT application no. PCT/JP2004/006417 filed on
`
`May 6, 2004 (hereinafter “Omura PCT”). All of the prior art references except for
`
`Mann were published or patented more than one year prior to May 6, 2004, and
`
`therefore qualify as prior art under 35 U.S.C. 102(b). Takahashi PCT was pub-
`
`lished on May 2, 2002. (ZEISS 1113, Cover Page.) Omura ‘387 was published on
`
`
`
`

`

`Petition for IPR of US 7,348,575
`Page 17
`April 18, 2003.2 (ZEISS 1111; ZEISS 1112, Cover Page.) Suwa issued in 1998.
`
`(ZEISS 1123.) Ulrich was published in 2002. (ZEISS 1118.) Asai was published in
`
`December 1993. (ZEISS 1115.)
`
`2. October 9, 2003, is the Earliest Priority Date to which
`the Omura Patent is Entitled
`
`Omura PCT claims benefit of three earlier filed Japanese applications: JP
`
`2003-128154, filed on May 6, 2003 (ZEISS 1107); JP 2003-350647, filed on Octo-
`
`ber 9, 2003 (ZEISS 1108); and JP 2003-364596, filed on October 24, 2003 (ZEISS
`
`1109). However, as explained below, the Challenged Claims are not entitled to the
`
`benefit of the May 6, 2003, priority date.
`
`Under 35 U.S.C. 119 (a), the claims in a U.S. application are entitled to the
`
`benefit of a foreign priority date or the filing date of a provisional application if the
`
`
`2 Under 35 U.S.C. § 119(a), “no patent shall be granted on any application for pa-
`
`tent for an invention which had been patented or described in a printed publication
`
`in any country more than one year before the date of the actual filing of the appli-
`
`cation in this country,” which is May 6, 2004, for the Omura Patent, the filing date
`
`of Omura PCT.
`
`
`
`

`

`Petition for IPR of US 7,348,575
`Page 18
`corresponding foreign application or provisional application supports the claims in
`
`the manner required by 35 U.S.C. § 112, first paragraph.3
`
`Independent claim 55 is directed to a catadioptric projection optical system
`
`that includes “a second unit … comprising at least four mirrors.” Because the other
`
`Challenged Claims all depend from claim 55, they similarly require “at least four
`
`mirrors.” It follows that in order for the Omura Patent to be accorded benefit of
`
`any of the three earlier filed Japanese applications, each Japanese application must
`
`separately provide a written description for a catadioptric projection optical system
`
`that includes at least four mirrors in accordance with 35 U.S.C. § 112, first para-
`
`graph.
`
`The earliest-filed priority application, JP 2003-128154, does not disclose any
`
`embodiments of catadioptric projection optical systems having “at least four mir-
`
`rors” as required by claims 55-67 of the Omura Patent. Rather, this application dis-
`
`closes only embodiments that have two mirrors. (See, generally, ZEISS 1107, and
`
`specifically FIGS. 5 and 7 which correspond to FIGS. 5 and 7 of the Omura Pa-
`
`tent.) Nor does JP 2003-128154 otherwise describe a catadioptric projection optical
`
`system having at least four mirrors as required by claims 55-67 in sufficient detail
`
`3 MPEP 2163.03 III, citing In re Ziegler, 992 F.2d 1197, 1200, 26 USPQ2d 1600,
`
`1603 (Fed. Cir. 1993); Kawaiv.Metlesics, 480 F.2d 880, 178 USPQ 158 (CCPA
`
`1973); In re Gosteli, 872 F.2d 1008, 10 USPQ2d 1614 (Fed. Cir. 1989).
`
`
`
`

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`Petition for IPR of US 7,348,575
`Page 19
`that one skilled in the art could reasonably conclude that Omura had possession of
`
`the alleged invention. (ZEISS 1116, ¶ 81.) Accordingly, JP 2003-128154 fails to
`
`provide a written description for the catadioptric projection optical systems cov-
`
`ered by claims 55-67, and these claims are not entitled to the benefit of priority of
`
`JP 2003-128154. Thus, the earliest date that these claims could be entitled to bene-
`
`fit of priority is October 9, 2003, the filing date of JP 2003-350647.
`
`3. Mann is Prior Art to the Omura Patent under 35
`U.S.C. § 102(e)
`
`Mann was filed on Aug. 12, 2003, prio