DOCKET NO.: 0107945.00246US24
`Filed By: Donald R. Steinberg, Reg. No. 37,241
`David L. Cavanaugh, Reg. No. 36,476
`Michael H. Smith, Reg. No. 71,190
`60 State Street
`Boston, Massachusetts 02109
`Tel: (617) 526-6000
`Email: Don.Steinberg@wilmerhale.com
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` David.Cavanaugh@wilmerhale.com
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` MichaelH.Smith@wilmerhale.com
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`UNITED STATES PATENT AND TRADEMARK OFFICE
`____________________________________________
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`
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`____________________________________________
`
`
`
`ASML Netherlands B.V., ASML US Inc., Excelitas Technologies Corp., and
`Qioptiq Photonics GmbH & Co. KG,
`Petitioners
`
`v.
`
`Energetiq Technology, Inc.,
`Patent Owner.
`
`Case IPR2016-00688
`
`
`
`PETITION FOR INTER PARTES REVIEW OF
`U.S. PATENT NO. 8,969,841
`CLAIMS 4, 5, 6, 8, and 26
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`

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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
`TABLE OF CONTENTS
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`Page
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`I. 
`
`MANDATORY NOTICES ............................................................................. 1 
`Real Parties-in-Interest .......................................................................... 1 
`A.
` 
`Related Matters ...................................................................................... 1 
`B.
` 
`Counsel .................................................................................................. 2 
`C.
` 
`Service Information ............................................................................... 2 
`D.
` 
`CERTIFICATION OF GROUNDS FOR STANDING .................................. 3 
`II. 
`III.  OVERVIEW OF CHALLENGE AND RELIEF REQUESTED .................... 3 
`  Grounds for Challenge .......................................................................... 3 
`A.
`Prior Art Patents and Printed Publications Relied Upon ...................... 3 
`B.
` 
`Relief Requested .................................................................................... 4 
`C.
` 
`IV.  PERSON OF ORDINARY SKILL IN THE ART .......................................... 4 
`V.  OVERVIEW OF THE ’841 PATENT ............................................................ 6 
`Summary of the Prosecution History .................................................... 7 
`A.
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`VI.  CLAIM CONSTRUCTION ............................................................................ 9 
`“Light source” ..................................................................................... 11 
`A.
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`“Laser Driven Light Source” ............................................................... 13 
`B.
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`“Substantially continuous laser” ......................................................... 14 
`C.
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`VII.  THE CHALLENGED CLAIMS ARE Unpatentable .................................... 14 
`Laser Sustained Plasma Light Sources Were Known Long
`A.
` 
`Before the Priority Date of the ’841 Patent ......................................... 15 
`Sustaining a plasma with a laser at various wavelengths,
`including in the range of 700-2000 nm, was well known in the
`art ......................................................................................................... 16 
`VIII.  GROUNDS FOR FINDING THE CHALLENGED CLAIMS INVALID ... 24 
`  Ground 1: Claims 4, 5, 6, 8, and 26 Are Unpatentable Over
`A.
`Gärtner in View of Mourou and Silfvast ............................................. 24 
`1. 
`Independent Claim 1 .................................................................... 24 
`2.  Dependent Claim 4 ....................................................................... 42 
`3.  Dependent Claim 5 ....................................................................... 43 
`
`B.
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`B.
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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
`4.  Dependent Claim 6 ....................................................................... 43 
`5.  Dependent Claim 8 ....................................................................... 44 
`6.  Dependent Claim 26 ..................................................................... 45 
`7.  Reasons to Combine for Claims 4-6, 8, and 26 ............................ 45 
`Ground 2: Claims 4-6, 8, and 26 Are Unpatentable Over
`Gärtner in View of Kensuke and Silfvast ........................................... 45 
`1. 
`Independent Claim 1 .................................................................... 47 
`2.  Dependent Claim 4 ....................................................................... 56 
`3.  Dependent Claim 5 ....................................................................... 56 
`4.  Dependent Claim 6 ....................................................................... 56 
`5.  Dependent Claim 8 ....................................................................... 57 
`6.  Dependent Claim 26 ..................................................................... 57 
`7.  Reasons to Combine for Claims 4-6, 8, and 26 ............................ 58 
`IX.  RESPONSE TO ARGUMENTS RAISED BY PATENT OWNER
`REGARDING OBJECTIVE INDICIA OF NON-OBVIOUSNESS ............ 58 
`CONCLUSION .............................................................................................. 60 
`
`X. 
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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
`
`I. MANDATORY NOTICES
` Real Parties-in-Interest
`A.
`ASML Netherlands B.V., ASML US Inc., Excelitas Technologies Corp., and
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`Qioptiq Photonics GmbH & Co. KG (“Petitioners”) are the real parties-in-interest.
`
`B.
`
` Related Matters
`U.S. Patent No. 8,969,841 (“the ’841 patent,” Ex. 1201) is one member of a
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`patent family of continuation and continuation in part applications. Exhibit 1202
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`shows the U.S. members of this patent family and the relationships among them.
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`Petitioners have already filed two petitions seeking inter partes review of claims 1-
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`3, 7, 10, 13, and 14 of the ’841 patent. On November 30, 2015, the Board
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`instituted an inter partes review on claims 1-3 and 7; the other petition remains
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`pending. (See Case No. IPR2015-01362 (PTAB Nov. 30, 2015)(Paper 12); Case
`
`No. IPR2016-00127 (pending)). Petitioners are also seeking inter partes review
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`of related U.S. Patent Nos. 7,435,982 (“the ’982 patent”); 7,786,455 (“the ’455
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`patent”); 8,309,943 (“the ’943 patent”); 8,525,138 (“the ’138 patent”); 9,048,000
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`(“the ’000 patent”); and U.S. Patent No. 9,185,786 (“the ’786 patent”) in Case Nos.
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`IPR2015-01300, IPR2015-01303, IPR2015-01377, IPR2016-00583, IPR2016-
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`00584, IPR2016-00585, IPR2015-01279, IPR2016-00570, IPR2016-00575,
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`IPR2015-00576, IPR2016-00578, IPR2016-00579, IPR2015-01277, IPR2016-
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`00554, IPR2016-00556, IPR2016-00555, IPR2015-01368, IPR2016-00565,
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`1
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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
`IPR2016-00566, IPR2015-01362, IPR2016-00127, IPR2015-01375, IPR2016-
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`00126, IPR2016-00771, and IPR2016-00776. The status of the other proceedings
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`is summarized in Ex. 1213.
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`Petitioners may also file additional petitions on the ’841, ’000, and ’786
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`patents. Petitioners request that the inter partes reviews of all these patents be
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`assigned to the same Panel for administrative efficiency.
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`The following litigation matters would affect or be affected by a decision in
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`this proceeding: Energetiq Tech., Inc. v. ASML Netherlands B.V., No. 1:15-cv-
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`10240-LTS (D. Mass.) and In the Matter of Certain Laser-Driven Light Sources,
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`Subsystems Containing Laser-Driven Light Sources, and Products Containing
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`Same, Inv. 337-TA-983 (U.S. International Trade Commission).
`
`C.
`
` Counsel
`Lead Counsel: Donald R. Steinberg (Registration No. 37,241)
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`Backup Counsel: David L. Cavanaugh (Registration No. 36,476)
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`Second Backup Counsel: Michael H. Smith (Registration No. 71,190)
`
`D.
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`Service Information
`
`
`Email: Donald R. Steinberg, don.steinberg@wilmerhale.com
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`Post and Hand Delivery: WilmerHale, 60 State St., Boston MA 02109
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`Telephone: 617-526-6453
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`
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`Facsimile: 617-526-5000
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`Petitioners consent to service by email.
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`2
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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
`II. CERTIFICATION OF GROUNDS FOR STANDING
`Petitioners certify pursuant to Rule 42.104(a) that the patent for which
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`review is sought is available for inter partes review and that Petitioners are not
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`barred or estopped from requesting an inter partes review challenging the patent
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`claims on the grounds identified in this Petition.
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`III. OVERVIEW OF CHALLENGE AND RELIEF REQUESTED
`Pursuant to Rules 42.22(a)(1) and 42.104 (b)(1)-(2), Petitioners challenge
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`claims 4, 5, 6, 8, and 26 of the ’841 patent (“the challenged claims”) and request
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`that each challenged claim be cancelled.
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`A.
`
` Grounds for Challenge
`This Petition, supported by the declaration of Dr. J. Gary Eden, a Professor
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`of Electrical Engineering at the University of Illinois (“Eden Decl.,” Ex. 1203),
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`demonstrates that there is a reasonable likelihood that Petitioners will prevail with
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`respect to at least one of the challenged claims and that each of the challenged
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`claims is unpatentable for the reasons cited in this petition. See 35 U.S.C. §
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`314(a).
`
`B.
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`Prior Art Patents and Printed Publications Relied Upon
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`Petitioners rely upon the following patents and printed publications:
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`1. French Patent Publication No. FR2554302A1, published May 3, 1985
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`(“Gärtner,” Ex. 1204), with English Translation, and is prior art to the ʼ841
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`patent under 35 U.S.C. § 102(b).
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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
`2. Int’l Publication WO-2004097520, published November 11, 2004 (“Mourou,”
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`Ex. 1214); prior art to the ʼ841 patent under 35 U.S.C. § 102(b).
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`3. Japanese Patent Publication No. 2006010675A, filed on February 24, 2005 and
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`published January 12, 2006 (“Kensuke,” Ex. 1205), with English Translation,
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`and is prior art to the ʼ841 patent under 35 U.S.C. §§ 102(a) and 102(b).
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`4. William T. Silfvast, Laser Fundamentals, 2d ed., published in 2004 (“Silfvast,”
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`Ex. 1206); prior art to the ʼ841 patent under 35 U.S.C. § 102(b).
`
`C.
`
` Relief Requested
`Petitioners request that the Patent Trial and Appeal Board cancel the
`
`challenged claims because they are unpatentable under 35 U.S.C. § 103.
`
`IV. PERSON OF ORDINARY SKILL IN THE ART
`A person of ordinary skill in the art (“POSITA”) at the time of the alleged
`
`invention of the ’841 patent would have had a Ph.D. in physics, electrical
`
`engineering, or an equivalent field and 2-4 years of work experience with lasers
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`and plasma, or a master’s degree in physics, electrical engineering, or an
`
`equivalent field and 4-5 years of work experience with lasers and plasmas. (Eden
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`Decl. ¶ 25 (Ex. 1203).)
`
`The ’841 patent states that the alleged “invention relates to methods and
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`apparatus for providing a laser-driven light source.” (’841 patent, 1:26-27 (Ex.
`
`1201).) Since a laser is fundamental to maintaining the plasma in all laser-driven
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`4
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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
`light sources (including the light source in the ’841 patent), it is reasonable to
`
`expect that a person skilled in the art would have experience with, and an
`
`understanding of, both plasmas and lasers. (Eden Decl. ¶ 26 (Ex. 1203).)
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`In accord with the definition of the skilled artisan suggested above, Dr.
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`Eden’s graduate students in 2005 (as well as before that time and since) normally
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`took graduate level courses in both lasers and plasma physics, and routinely
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`worked with (and were instructed in the laboratory about the properties of)
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`plasmas, many of which were produced with lasers. Lasers sufficiently powerful
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`to generate and/or sustain a plasma are a potential safety hazard and must be
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`approached with skill. Fundamental safety concerns require those in the field of
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`systems incorporating plasmas and lasers to understand both from a fundamental
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`perspective and to acquire experience in working with both. Furthermore, because
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`the properties of individual lasers determine if they are suitable for driving an
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`efficient plasma light source, one skilled in the art must have an understanding of
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`the state of the art in laser physics and technology, as well as the parameters and
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`characteristics of the most efficient and powerful systems. By the time Dr. Eden’s
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`graduate students obtained their Ph.D. degrees, therefore, they would have had at
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`least 4-5 years of experience with both plasmas and lasers. Thus, the problem and
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`solution to which the ’841 patent is directed, and the experience of those who
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`typically would work on developing laser-generated plasmas, demonstrate that a
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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
`person of ordinary skill would have experience with both lasers and plasmas.
`
`(Eden Decl. ¶ 27 (Ex. 1203).)
`
`V. OVERVIEW OF THE ’841 PATENT
`The ’841 patent family is directed to a laser sustained plasma light source for
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`use in, e.g., testing and inspection for semiconductor manufacturing. As shown in
`
`Fig. 1, the light source includes a sealed pressurized chamber containing gas, an
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`ignition source for ionizing the gas, a laser providing energy to the plasma, a
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`plasma-generated light, and the chamber having a transparent region to allow the
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`plasma-generated light to exit. The ’841 continuation adds claims that require that
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`the laser operate within a wavelength range of 700-2000 nm. (’841 patent, claim 1
`
`(Ex. 1201).) (Eden Decl. ¶ 28 (Ex. 1203).)
`
`As discussed below, there was nothing new in 2006 about sustaining a
`
`plasma with a laser to produce light. Multiple prior art references, including
`
`Gärtner, Mourou, and Kensuke disclosed laser-sustained plasma light sources.
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`Moreover, there was nothing new about providing energy to a plasma with a laser
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`operating within a range of 700-2000 nm. As the patent admits, efficient, cost
`
`effective, and high power lasers in the claimed wavelength range were “recently
`
`available.” (’841 patent, 16:6-14 (emphasis added) (Ex. 1201).) Mourou and
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`Kensuke provide examples of systems that provide energy to a plasma with a laser
`
`operating within a range of 700-2000 nm, while Gärtner provides an example of a
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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
`system that maintains a plasma. Silfvast shows that the laser used by Mourou and
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`Kensuke could be operated as a continuous wave laser. It would have been obvious
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`to combine Mourou and Silfvast or Kensuke and Silfvast with Gärtner to arrive at
`
`the claimed invention. (Eden Decl. ¶ 30 (Ex. 1203).)
`
`A.
`
`
`
`Summary of the Prosecution History
`
`The ’841 patent (Ex. 1201) issued from U.S. Patent Appl. No. 14/510,959,
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`filed on October 9, 2014. The ’841 patent is a continuation of the ’000 patent,
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`which is a continuation of the ’138 patent, which is a continuation in part of U.S.
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`Pat. Appl. No. 12/166,918 (now U.S. 7,989,786), which is a continuation in part of
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`the ’455 patent, which is a continuation in part of the ’982 patent, filed March 31,
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`2006. (See Ex. 1202.) As explained below, the Examiner allowed the claims of
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`the ʼ841 patent only after the applicant amended the claims to include a limitation
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`requiring the laser wavelength range to be between about 700 nm to 2000 nm.
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`On November 12, 2014, the Examiner rejected the claims in light of various
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`prior art references. (Office Action dated Nov. 12, 2014 (Ex. 1208).) The claims
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`were primarily rejected based on Cross and Kane. The Office Action asserted that
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`Cross discloses a light source comprising a pressurized chamber in which a laser
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`sustained plasma emits light, and that Kane discloses an ultraviolet light source
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`comprising a pressurized chamber and an electrode ignition source. (Id. at 2-4.)
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`On December 17, 2014, the applicant amended the claims to add features
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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
`such as a “sealed” chamber, pressure above 10 atm, wavelength ranges for the laser
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`and the light produced by the plasma, and a chamber that is transparent/includes
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`windows. (Applicant’s Amendment and Response at 3, dated Dec. 17, 2014 (Ex.
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`1209).) The applicant argued that the amended claims were distinct from the prior
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`art because allegedly “none of the references of record produce a plasma generated
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`light having output wavelengths greater than 50 nm.”1 (Id. at 10.)
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`On January 22, 2015, the newly amended claims were allowed. (Notice of
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`Allowability at 2, Jan. 22, 2015 (Ex. 1210).) With respect to application claims 1,
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`15, and 20, the Examiner introduced U.S. Publ. No. 2006/0152128 (“Manning”)
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`but noted that Manning did not disclose the use of a laser with a wavelength from
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`700-2000 nm to create a plasma that produced a light with a wavelength greater
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`than 50 nm. (Id.) Regarding Cross, the Examiner stated that in addition to not
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`disclosing a laser with a wavelength from 700-2000 nm, the reference did not
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`disclose a transparent region of the chamber and was concerned with producing
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`ions instead of light produced by a plasma. (Id. at 2-3.) The Examiner also stated
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`that it would not have been obvious to combine Manning and Cross because “they
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`1 Patent Owner was in fact mistaken. For example, Kane discloses a “plasma
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`lamp” that is “capable of providing a source of high-peak-power incoherent
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`ultraviolet (UV) light (80-350 nm, more typically 11-320 nm).” (U.S. 6,541,924
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`(“Kane”) at 7:53-59 (Ex. 1218).) (Eden Decl. ¶ 26 n. 1 (Ex. 1203).)
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`8
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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
`belong to different fields of endeavor; namely, Manning uses a plasma to generate
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`light, while Cross uses a plasma to generate ions.” (Id. at 3.) The Examiner,
`
`however, did not consider Gärtner or Mourou or Silfvast, nor was the Examiner
`
`provided a complete English translation of Kensuke.2 As discussed below, (i)
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`Gärtner in view of Mourou and Silfvast and (ii) Gärtner in view of Kensuke and
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`Silfvast each renders the challenged claims unpatentable as obvious.
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`The independent claim features identified in the Notice of Allowability as
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`missing from the prior art are present in the prior art used in the proposed grounds
`
`of unpatentability, as the Board recognized in its Decision on Institution in an IPR
`
`directed to the same patent. (Case No. IPR2015-01362 at 13-14 (PTAB Nov. 30,
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`2015) (Paper 12) (instituting on claims including independent claim 1).)
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`VI. CLAIM CONSTRUCTION
`A claim in inter partes review is given the “broadest reasonable construction
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`2 Kensuke (JP 2006-10675) was included in an Information Disclosure Statement
`
`filed by applicant on October 9, 2014. However, applicant only submitted an
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`English translation of the abstract and Kensuke was not used in any of the
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`Examiner’s rejections. Notably, as described further below, Kensuke discloses the
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`use of a laser with a wavelength from 700-2000 nm to create a plasma that
`
`produced a light with a wavelength greater than 50 nm, but the abstract does not
`
`provide this disclosure. (See infra at section VIII.B.1.d).)
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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
`in light of the specification of the patent in which it appears.” 37 C.F.R. §
`
`42.100(b). Claim terms are given their ordinary and customary meaning as would
`
`be understood by a person of ordinary skill in the art at the time of the invention
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`and in the context of the patent disclosure. In re Translogic Tech., Inc., 504 F.3d
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`1249, 1257 (Fed. Cir. 2007). If the specification sets forth an alternate definition
`
`of a term with reasonable clarity, deliberateness, and precision, the patentee’s
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`lexicography governs. In re Paulsen, 30 F.3d 1475, 1480 (Fed. Cir. 1994).
`
`Should the Patent Owner, seeking to avoid the prior art, contend that the
`
`claims have a construction different from their broadest reasonable construction,
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`the appropriate course is for the Patent Owner to seek to amend the claims to
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`expressly correspond to its contentions in this proceeding. See 77 Fed. Reg.
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`48,764; 48,766-67 (Aug. 14, 2012).
`
`Consistent with this standard, this section proposes, under the broadest
`
`reasonable construction standard, constructions of terms and provides support for
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`these proposed constructions. Terms not included in this section have their
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`broadest reasonable meaning in light of the specification as commonly understood
`
`by those of ordinary skill.
`
`Applying the claim construction standard of Phillips v. AWH Corp., 415
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`F.3d 1303 (Fed. Cir. 2005) would not change the analysis or conclusions covered
`
`in this petition. The prior art teaches each claim limitation under any reasonable
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`10
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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
`interpretation of the claim terms, and the analysis is not dependent on application
`
`of the “broadest reasonable interpretation” standard.
`
`A.
`
`“Light source”
`
`
` The term “light source” is recited in all challenged claims. “Light source”
`
`should be construed to mean “a source of electromagnetic radiation in the
`
`ultraviolet (“UV”), extreme UV, vacuum UV, visible, near infrared, middle
`
`infrared, or far infrared regions of the spectrum, having wavelengths within the
`
`range of 10 nm to 1,000 μm.” (Eden Decl. ¶ 38 (Ex. 1203).)
`
`The ordinary and customary meaning of “light source”3 is a source of
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`electromagnetic radiation in the extreme UV (10 nm to 100 nm), vacuum UV (100
`
`nm to 200 nm), ultraviolet (200 nm to 400 nm), visible (400 to 700 nm), near-
`
`infrared (700 nm to 1,000 nm (1µm)), middle infrared (1 µm to 10 µm), or far
`
`infrared (10 µm to 1,000 µm) regions of the spectrum. (See, e.g., William T.
`
`Silfvast, Laser Fundamentals 4 (2d ed. 2004) (Ex. 1206).) The Patent Owner
`
`publishes a data sheet which is consistent with the ordinary and customary
`
`3 The term “light” is sometimes used more narrowly to refer only to visible light.
`
`However, references to “ultraviolet light” in the ’841 patent make clear that the
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`broader meaning is intended because ultraviolet light has a wavelength shorter than
`
`that of visible light. (See, e.g., ’841 patent, 7:52; 17:13; 18:43; 20:32-33; 23:29;
`
`26:33) (Ex. 1201).) (See Eden Decl. ¶ 32 n. 3 (Ex. 1203).)
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`11
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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
`meaning in considering EUV [Extreme Ultraviolet] to be within the meaning of
`
`“light source.” (See, e.g., Energetiq EQ-10M Data Sheet at 2 (describing
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`Energetiq’s EQ-10M product operating at 13.5 nm as an “EUV Light Source”)
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`(Ex. 1207).) (Eden Decl. ¶ 39 (Ex. 1203).)
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`The ’841 patent does not provide a definition for “light source” and uses the
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`term consistent with the ordinary and customary meaning of the term. The ’841
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`patent states that parameters such as the wavelength of the light from a light source
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`vary depending upon the application. (’841 patent, 1:39-41 (Ex. 1201).) The
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`specification describes “UV light” as an example of the type of light that can be
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`generated: “emitted light 136 (e.g., at least one or more wavelengths of UV light).”
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`(’841 patent, 18:34-36 (Ex. 1201); see also id. at 17:12-14 (discussing the UV light
`
`136 generated by the plasma 132 of the light source 100).) Therefore, the term
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`“light source” should be construed to mean “a source of electromagnetic radiation
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`in the ultraviolet (“UV”), extreme UV, vacuum UV, visible, near infrared, middle
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`infrared, or far infrared regions of the spectrum, having wavelengths within the
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`range of 10 nm to 1,000 μm.” 4 (Eden Decl. ¶¶ 40-41 (Ex. 1203).)
`
`4 The particular construction for “light source” was adopted by the Board in the
`
`Decision granting Institution of Inter Partes Review for claims 1-3 and 7. (See
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`Case No. IPR2015-01362 (PTAB Nov. 30, 2015) (Paper 12).) This construction is
`
`equivalent to the Petitioners’ prior proposed construction for the term “light
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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
`
`B.
`
`“Laser Driven Light Source”
`
`
`The term “laser driven light source” is recited in all challenged claims. The
`
`term “laser driven light source” should be construed to mean a “light source having
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`a laser applying energy to generate light.” (Eden Decl. ¶ 42 (Ex. 1203).)
`
`The term “laser driven light source” is not a term of art. As used in the ’841
`
`patent, a person of skill in the art would have understood the term “laser driven
`
`light source” to refer to light sources in which a laser supplies energy to generate
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`light. (See e.g., ’841 patent, 14:45-50, 63-65 (“The light source 100 also includes
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`at least one laser source 104 that generates a laser beam that is provided to the
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`plasma 132 located in the chamber 128 to initiate and/or sustain the high brightness
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`light 136. . . . It is also desirable for the laser source 104 to drive and/or sustain the
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`plasma with a high power laser beam.”) (Ex. 1201).) Therefore, the term “laser
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`driven light source” should be construed to mean a “light source having a laser
`
`applying energy to generate light.”5 (Eden Decl. ¶ 43 (Ex. 1203).)
`
`source” in the prior Petitions for the ’841 patent and other patents in the family.
`
`5 The particular construction for the claim term “laser driven light source” was
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`adopted by the Board in the Decision granting Institution of Inter Partes Review
`
`for claims 1-3 and 7. (See Case No. IPR2015-01362 (PTAB Nov. 30, 2015) (Paper
`
`12).) This construction is equivalent to the Petitioners’ prior proposed construction
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`for the term “laser driven light source” in the prior Petitions for the ’841 patent and
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`13
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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
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`C.
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`“Substantially continuous laser”
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`
`The term “substantially continuous laser” is recited in independent claim 1,
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`from which the challenged claims depend. The term “substantially continuous
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`laser” should be construed to encompass a continuous wave laser, a high pulse rate
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`laser, and a laser that provides substantially continuous laser energy, as the Board
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`construed the term in its Decision granting Institution of Inter Partes Review for
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`claims 1-3 and 7. (See Case No. IPR2015-01362 (PTAB Nov. 30, 2015) (Paper
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`12).) (Eden Decl. ¶ 44 (Ex. 1203).)
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`The specification of the ’841 patent indicates that a substantially continuous
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`laser can be a continuous wave laser, a high pulse rate laser, or a laser that provides
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`substantially continuous laser energy. (’841 patent, 15:60-62 (high pulse rate laser
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`or continuous wave laser); 16:15-18 (“high pulse rate laser source that provides
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`substantially continuous laser energy”); 4:53-55 (a “continuous-wave laser emits
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`radiation continuously or substantially continuously rather than in short bursts, as
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`in a pulsed laser”) (Ex. 1201).) (Eden Decl. ¶ 45 (Ex. 1203).)
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`VII. THE CHALLENGED CLAIMS ARE UNPATENTABLE
`Challenged claims 4, 5, 6, 8, and 26 of the ʼ841 patent recite and claim
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`features that were known in the art prior to the earliest priority date, and are
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`obvious in view of the prior art.
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`other patents in the patent family.
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`14
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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
` Laser Sustained Plasma Light Sources Were Known Long Before
`the Priority Date of the ’841 Patent
`
`A.
`
`When the application that led to the ’841 patent was filed, there was nothing
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`new about a light source using an ignition source to generate a plasma in a
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`pressurized chamber and a laser operating at certain wavelengths to sustain the
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`plasma to produce light at certain wavelengths. This concept had been known and
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`widely used since at least as early as the 1980s, more than two decades before the
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`application date. For example, in 1983, Gärtner filed a patent application which
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`published in 1985. (Eden Decl. ¶ 47 (Ex. 1203).)
`
`
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`’841 patent, Fig. 1 (Ex. 1201)
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`
`
`
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`Gärtner, Fig. 1 (Ex. 1204)
`
`As shown in Fig. 1, reproduced above adjacent to Fig. 1 of the ’841 patent,
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`Gärtner discloses a light source with the same features claimed in the ’841 patent:
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`(1) a sealed chamber 1 (green); (2) transparent region of a chamber so that the light
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`could exit the chamber – window 8; (3) an ignition source - pulsed laser 10 (blue),
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`15
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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
`which generates a plasma 14 (yellow); and (4) a laser to produce light - laser 9
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`(red), which provides energy to the plasma 14 (yellow) and produces light 15
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`having a wavelength greater than 50 nm. (Gärtner at 4:32-5:9, 5:26-30, 6:10-12,
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`Fig. 1 (Ex. 1204).) (Eden Decl. ¶ 47 (Ex. 1203).)
`
`
`
`B.
`
`Sustaining a plasma with a laser at various wavelengths, including
`in the range of 700-2000 nm, was well known in the art
`Gärtner’s laser 9 is a CO2 laser. (Gärtner at 5:3-5 (Ex. 1204).) CO2 lasers,
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`which generally operate at a wavelength of 10.6 µm, were commonly used during
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`the ‘70s and ‘80s because they provided high power and were cost-effective at the
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`time. (See, e.g., Cross at 5:44-47 (“Carbon dioxide lasers have been used since the
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`output therefrom is readily absorbed by plasmas and they are available with very
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`high power in both pulsed and cw operating modes.”) (Ex. 1215).) However, it
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`was recognized around the time of Gärtner that shorter wavelength lasers could
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`also be used. (See, e.g., id. at 5:40-53 (“[L]asers other than carbon dioxide may be
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`used for the initiation and the sustaining of the continuous optical discharge
`
`plasma. For example, a Nd:YAG laser has been used for the initiation step. . . .
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`Moreover, laser heating of plasma via the inverse Bremsstrahlung process varies as
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`λ2, so that cw-laser sources having shorter wavelengths such as Nd:Yag, for
`
`example, are absorbed less effectively, and would require substantially greater cw-
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`laser output power levels to sustain the plasma.”) (Ex. 1215).) By the mid-2000s,
`
`laser technology for shorter wavelengths (e.g., those in the range of 700-2000 nm)
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`16
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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
`had improved significantly because of the development of titanium-doped sapphire
`
`and rare earth-doped glass fiber lasers (in particular), making it easier and more
`
`desirable to sustain plasmas with lasers in this wavelength range6. For example,
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`“Since the mid-1990s, high power Yb-doped fiber lasers have progressed rapidly
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`from 2 W in 1995, to 20 W and 35 W in 1997, and 110 W in 1999, the published
`
`record at the time of this writing.” (Digonnet, 148 (references omitted) (Ex.
`
`1222).) The ytterbium (Yb)-doped glass fiber laser typically operates at a
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`wavelength of approximately 1030 nm. By 2004, titanium-doped lasers were
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`6 Patent Owner alleges that suitable commercial short wavelength lasers were
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`available for more than 20 years before the invention. (Case No. IPR2015-01362 at
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`3, 37, 50-52 (PTAB Mar. 1, 2016) (Paper 24).) However, the lasers that Patent
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`Owner cites as examples (as well as other industrial, high-power, solid-state lasers,
`
`available prior to the late 1990s), were generally inefficient, costly, heavy, bulky,
`
`and exhibited poor beam quality, rendering them unsuitable for commercial laser-
`
`driven light sources. Indeed, Zimakov (cited by Patent Owner in IPR2015-01375,
`
`directed to the’841 patent), acknowledges that “plasma-based light source[s]” that
`
`are “used in micro-electronics …became possible due to the appearance of high-
`
`efficiency near-IR lasers, in particular diode lasers and ytterbium fiber lasers.”
`
`(Zimakov, 68 (citing papers from 2006 and later) (Ex. 1227).) (Eden Decl. ¶ 49
`
`n.6 (Ex. 1203).)
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`17
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`U.S. Patent 8,969,841
`Petition for Inter Partes Review
`available that also produced at least 50 watts of power over a broad range of
`
`wavelengths in the near-infrared and middle infrared regions (660-1180 nm).
`
`(Silfvast, 567 (Ex. 1206).) In 2004, it was also shown that 1,000 W (1 kW) could
`
`be obtained from a ytterbium-doped fiber laser. (Jeong, 1 (disclosing a
`
`“[y]tterbium-doped large-core fibre laser with 1 kW of [cw] output power”) (Ex.
`
`1228).) Furthermore, it was known by the 1990s that such high power fiber lasers
`
`could be tuned to wavelengths between 970 nm and 1200 nm. (See Pask, 2 (Ex.
`
`1229).) It quickly became evident that such “diode-pumped” lasers were
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`considerably more efficient and compact than their lamp-pumped counterparts of
`
`the past. As