DOCKET NO.: 0107945.00235US21
`Filed By: Donald 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
`
` David.Cavanaugh@wilmerhale.com
`
` MichaelH.Smith@wilmerhale.com
`
`UNITED STATES PATENT AND TRADEMARK OFFICE
`____________________________________________
`
`
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`____________________________________________
`
`
`
`ASML NETHERLANDS B.V., EXCELITAS TECHNOLOGIES CORP., AND QIOPTIQ
`PHOTONICS GMBH & CO. KG,
`Petitioners
`
`v.
`
`ENERGETIQ TECHNOLOGY, INC.,
`Patent Owner.
`
`Case IPR2016-00576
`
`
`
`PETITION FOR INTER PARTES REVIEW OF
`U.S. PATENT NO. 7,786,455
`CLAIMS 17, 18
`
`
`
`
`
`
`
`

`
`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`TABLE OF CONTENTS
`
`
`I. 
`
`MANDATORY NOTICES ............................................................................. 1 
`A. 
`Real Parties-in-Interest .......................................................................... 1 
`B. 
`Related Matters ...................................................................................... 1 
`C. 
`Counsel .................................................................................................. 2 
`D. 
`Service Information ............................................................................... 2 
`CERTIFICATION OF GROUNDS FOR STANDING .................................. 3 
`II. 
`III.  OVERVIEW OF CHALLENGE AND RELIEF REQUESTED .................... 3 
`A.  Grounds for Challenge .......................................................................... 3 
`B. 
`Prior Art Patents and Printed Publications Relied Upon ...................... 3 
`C. 
`Relief Requested .................................................................................... 4 
`IV.  PERSON OF ORDINARY SKILL IN THE ART .......................................... 4 
`V.  OVERVIEW OF THE ’455 PATENT ............................................................ 4 
`A. 
`Summary of the Prosecution History .................................................... 7 
`VI.  CLAIM CONSTRUCTION ............................................................................ 8 
`A. 
`“Light source” ....................................................................................... 9 
`B. 
`“High brightness light” ........................................................................ 11 
`VII.  THE CHALLENGED CLAIMS ARE INVALID ......................................... 15 
`A. 
`Laser Sustained Plasma Light Sources Were Known Long
`Before the Priority Date of the ’455 Patent ......................................... 15 
`Using a dichroic mirror to separate light of different
`wavelengths was well known in the art. .............................................. 18 
`VIII.  GROUNDS FOR FINDING THE CHALLENGED CLAIMS INVALID ... 19 
`A.  Ground 1: Claim 17 is unpatentable over Gärtner .............................. 19 
`(a)  Gärtner is prior art that was not considered by the Patent Office
`during examination. ...................................................................... 20 
`(b)  Claim 17 is Obvious over Gärtner ................................................ 20 
`a)  Claim 17 - Preamble (element [17p]) ................................... 20 
`b)  Claim 17 - Chamber & Reflective Surface (element [17a]) . 21 
`
`B. 
`
`i
`
`

`
`B. 
`
`C. 
`
`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`c)  Claim 17 - Ignition Source (element [17b]) ......................... 22 
`d)  Claim 17 - Laser (element [17c]) ........................................ 22 
`e)  Claim 17 - Reflector (element [17d]) .................................. 24 
`f)  Reasons to combine ............................................................... 26 
`Ground 2: Claim 18 is unpatentable over Gärtner in view of Ito ....... 28 
`(a)  Gärtner and Ito are each prior art that was not considered by the
`Patent Office during examination. ............................................... 28 
`(b)  Dependent Claim 18 is unpatentable over Gärtner in view of Ito 28 
`a)  Claim 18 ................................................................................ 28 
`b)  Reasons to combine .............................................................. 34 
`Ground 3: Claim 17 is unpatentable over Gärtner in view of
`Ershov .................................................................................................. 37 
`(a)  Gärtner and Ershov are each prior art that was not considered by
`the Patent Office during examination. .......................................... 37 
`(b)  Claim 17 is unpatentable over Gärtner in view of Ershov ........... 38 
`(c)  Reasons to combine ...................................................................... 40 
`D.  Ground 4: Claim 18 is unpatentable over Gärtner in view of
`Ershov and further in view of Ito ........................................................ 44 
`(a)  Claim 18 ....................................................................................... 44 
`(b)  Reasons to combine ...................................................................... 45 
`IX.  RESPONSE TO ARGUMENTS RAISED BY PATENT OWNER IN ITS
`PRELIMINARY INJUNCTION MOTION .................................................. 46 
`A. 
`Patent Owner’s Arguments Regarding the Content of the Prior
`Art ........................................................................................................ 46 
`(a)  High Brightness Light .................................................................. 46 
`Patent Owner’s Arguments Regarding Objective Indicia of
`Non-Obviousness ................................................................................ 51 
`CONCLUSION .............................................................................................. 53 
`
`B. 
`
`X. 
`
`
`
`
`
`
`
`
`ii
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`

`
`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`
`I. MANDATORY NOTICES
`A. Real Parties-in-Interest
`ASML Netherlands B.V., Excelitas Technologies Corp., and Qioptiq
`
`Photonics GmbH & Co. KG (“Petitioners”) are the real parties-in-interest.
`
`B. Related Matters
`U.S. Patent No. 7,786,455 (“the ’455 patent,” Ex. 1301) is one member of a
`
`patent family of continuation, continuation in part, and divisional applications.
`
`Exhibit 1302 shows the U.S. members of this patent family and the relationships
`
`among them. Petitioners have already filed petitions seeking inter partes review of
`
`the ’455 patent, and of related U.S. Patent Nos. 7,435,982 (“the ’982 patent”);
`
`8,309,943 (“the ’943 patent”); 8,525,138 (“the ’138 patent”); 8,969,841 (“the ’841
`
`patent”); and 9,048,000 (“the ’000 patent”), as summarized below:
`
`IPR No.
`
`Challenged Claims
`
`Status
`
`Patent
`No.
`7,435,982
`
`IPR2015-01300
`IPR2015-01303
`
`1, 3-4, 10, 16, 21, 24-
`27, 30, 31, 34, 37, 42-
`43, 49, 55, 61-64, 67,
`68, 71, 72, 74, and 78
`23 and 60
`
`7,435,982
`
`IPR2015-01377
`
`7,786,455
`
`IPR2015-01279
`
`19, 39-41
`
`8,309,943
`
`IPR2015-01277
`
`1, 3, 13, and 16
`
`8,525,138
`
`IPR2015-01368
`
`1-5
`
`8,969,841
`
`IPR2015-01362
`
`1, 2, 3, and 7
`
`1
`
`Instituted on all
`challenged claims
`
`Instituted on all
`challenged claims
`Instituted on all
`challenged claims
`Instituted on all
`challenged claims
`Instituted on all
`challenged claims
`Instituted on all
`challenged claims
`
`

`
`8,969,841
`9,048,000
`
`IPR2016-00127
`IPR2015-01375
`
`10, 13, 14
`1, 15, and 18
`
`9,048,000
`
`
`IPR2016-00126
`
`7-10
`
`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`Pending
`Instituted on all
`challenged claims
`Pending
`
`Petitioners are also filing additional petitions on the ’455, ’982, ’943, ʼ138,
`
`’841, and ’000 patents, as well as on the related U.S. Patent No. 9,185,786 (“the
`
`’786 patent”). Petitioners request that the inter partes reviews of all the ’455, ’982,
`
`’943, ’138, ’841, ’000, and ’786 patents be assigned to the same Panel for
`
`administrative efficiency.
`
`The following litigation matters would affect or be affected by a decision in
`
`this proceeding: Energetiq Tech., Inc. v. ASML Netherlands B.V., et al, Civil
`
`Action No. 1:15-cv-10240-LTS (D. Mass.) and In the Matter of Certain Laser-
`
`Driven Light Sources, Subsystems Containing Laser-Driven Light Sources, and
`
`Products Containing Same, Inv. No. 337-TA-983.
`
`C. Counsel
`Lead Counsel: Donald R. Steinberg (Registration No. 37,241)
`
`First Backup Counsel: David L. Cavanaugh (Registration No. 36,476)
`
`Second Backup Counsel: Michael H. Smith (Registration No. 71,190)
`
`Service Information
`
`D.
`Email: Donald R. Steinberg, don.steinberg@wilmerhale.com
`
`Post and Hand Delivery: WilmerHale, 60 State St., Boston, MA 02109
`
`2
`
`

`
`Telephone: 617-526-6453
`
`
`
`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`Facsimile: 617-526-5000
`
`II. CERTIFICATION OF GROUNDS FOR STANDING
`Petitioners certify pursuant to Rule 42.104(a) that the patent for which
`
`review is sought is available for inter partes review and that Petitioners are not
`
`barred or estopped from requesting an inter partes review challenging the patent
`
`claims on the grounds identified in this Petition.
`
`III. OVERVIEW OF CHALLENGE AND RELIEF REQUESTED
`Pursuant to Rules 42.22(a)(1) and 42.104 (b)(1)-(2), Petitioners challenge
`
`claims 17 and 18 of the ’455 patent (“the challenged claims”) and request that each
`
`challenged claim be cancelled.
`
`A. Grounds for Challenge
`This Petition, supported by the declaration of Dr. Howard Milchberg, a
`
`Professor of Physics and Electrical and Computer Engineering at the University of
`
`Maryland in College Park, Maryland (“Milchberg Decl.,” Ex. 1303), demonstrates
`
`that there is a reasonable likelihood that Petitioners will prevail with respect to at
`
`least one of the challenged claims and that each of the challenged claims is
`
`unpatentable for the reasons cited in this petition. See 35 U.S.C. § 314(a). As
`
`detailed in the grounds of unpatentability below, the challenged claims are
`
`unpatentable under 35 U.S.C. § 103.
`
`Prior Art Patents and Printed Publications Relied Upon
`
`B.
`Petitioners rely upon the following patents and printed publications:
`
`3
`
`

`
`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`1. French Patent Publication No. FR2554302A1 (with English Translation),
`
`published May 3, 1985 (“Gärtner,” Ex. 1304), and is prior art to the ʼ455 patent
`
`under 35 U.S.C. § 102(b).
`
`2. Japanese Patent Publication No. JPH04-144053A, (with English Translation),
`
`published May 18, 1992 (“Ito,” Ex. 1305), and is prior art to the ʼ455 patent
`
`under 35 U.S.C. § 102(b).
`
`3. U.S. Patent Publication No. 2006/0192152, filed August 31, 2005, published
`
`August 31, 2006 (“Ershov,” Ex. 1316), and is prior art to the ʼ455 patent under
`
`35 U.S.C. § 102(e).
`
` Relief Requested
`
`C.
`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 skill in the art at the time of the alleged invention of the ’455
`
`patent would have had a Ph.D. in physics, electrical engineering, or an equivalent
`
`field and 2-4 years of work experience with lasers 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 plasma. (Milchberg Decl. ¶ 21 (Ex. 1303).)
`
`V. OVERVIEW OF THE ’455 PATENT
`The ’455 patent is directed to a laser sustained plasma light source for use in,
`
`4
`
`

`
`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`for example, testing and inspection for semiconductor manufacturing. As depicted
`
`in Fig. 1, shown below, the light source includes a chamber (green), an ignition
`
`source (blue) for igniting a plasma, and a laser (red) for providing energy to the
`
`plasma to produce light. (’455 patent at 4:25-7:34 (Ex. 1301).) (Milchberg Decl.
`
`¶ 22 (Ex. 1303).)
`
`
`
`’455 patent Fig. 1 (Ex. 1301) (Annotated)
`
`The ’455 patent also describes the use of reflectors for reflecting or
`
`transmitting light and energy. For example, as illustrated in Figure 5, below,
`
`reflective surface 540 (purple) can direct laser energy to the plasma in the chamber
`
`and direct emitted light towards the output. (’455 patent at 13:10-29 (Ex. 1301).)
`
`Additionally, reflector 512 (orange) reflects the laser beam 520 toward the
`
`reflective surface 540 (purple) of the chamber and the reflector 512 (orange) is
`
`substantially transparent to plasma light 536. (Id.) (Milchberg Decl. ¶ 23 (Ex.
`
`1303).)
`
`5
`
`

`
`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`
`’455 patent Fig. 5 (Ex. 1301) (Annotated)
`
`
`
`According to the ’455 patent, prior art light sources relied upon electrodes to
`
`both generate and sustain the plasma, which resulted in wear and contamination.
`
`(’455 patent, 1:28-44 (Ex. 1301).) Thus, a need allegedly arose for a way to
`
`sustain a plasma without relying on an electrical discharge from electrodes. (’455
`
`patent, 1:45-49 (Ex. 1301).) The purported invention involves using a laser to
`
`provide energy to sustain the plasma to produce a “high brightness” light source.
`
`(See, e.g., ’455 patent, 1:57-59 (Ex. 1301).) Additionally, the purported invention
`
`also involves different configurations of reflectors to direct laser energy and
`
`plasma light. (’455 patent, 4:25-7:34 (Ex. 1301).) (Milchberg Decl. ¶ 24 (Ex.
`
`1303).)
`
`As discussed below, sustaining a plasma with a laser to produce high
`
`brightness light and using configurations of reflectors to direct laser energy and
`
`plasma light was not new in 2007. Multiple prior art references, including Gärtner
`
`6
`
`

`
`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`and Ershov, disclosed laser-sustained plasma light sources with the same elements
`
`as the ’455 patent: a chamber, an ignited plasma, a laser, and reflective surfaces.
`
`(Milchberg Decl. ¶ 25 (Ex. 1303).)
`
`Furthermore, there was nothing new about using a dichroic mirror to
`
`separate out (a) light from a laser beam, and (b) light emitted from a target
`
`irradiated by the laser. For example, Ito disclosed using a dichroic mirror to
`
`separate out light in this fashion. (Milchberg Decl. ¶ 26 (Ex. 1303).)
`
`A.
`
`Summary of the Prosecution History
`
`The ’455 patent issued from U.S. Patent Appl. No. 11/695,348, filed on
`
`April 2, 2007. On May 4, 2010, all the claims were allowed without a rejection
`
`based on prior art. The Notice of Allowability provided several reasons for
`
`allowance, including a statement that the invention involved igniting a gas within a
`
`chamber with a reflective surface and providing laser energy to the ionized gas in
`
`the chamber to produce a plasma that generates high brightness light. (Notice of
`
`Allowability dated May 4, 2010, at 3-4 (Ex. 1306).) The ’455 patent issued on
`
`August 31, 2010. (Milchberg Decl. ¶ 27 (Ex. 1303).)
`
`The independent claim features identified in the Notice of Allowability as
`
`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. IPR2015-01279, slip op. at 12 (PTAB Nov.
`
`7
`
`

`
`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`30, 2015) (Paper 13).). (Milchberg Decl. ¶ 28 (Ex. 1303).)
`
`VI. CLAIM CONSTRUCTION
`A claim in inter partes review is given the “broadest reasonable construction
`
`in light of the specification of the patent in which it appears.” 37 C.F.R. §
`
`42.100(b); see Office Patent Trial Practice Guide, 77 Fed. Reg. 48,756, at 48,764,
`
`48,766 (Aug. 14, 2012). 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 and in the context of the entire patent disclosure. In re Translogic
`
`Tech., Inc., 504 F.3d 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 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,
`
`the appropriate course is for the Patent Owner to seek to amend the claims to
`
`expressly correspond to its contentions in this proceeding. See 77 Fed. Reg. at
`
`48,766-67.
`
`Consistent with this standard, this section proposes, under the broadest
`
`reasonable construction standard, constructions of terms and provides support for
`
`these proposed constructions. Terms not included in this section have their
`
`8
`
`

`
`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`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
`
`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
`
`interpretation of the claim terms, and the analysis is not dependent on application
`
`of the "broadest reasonable interpretation" standard. (Milchberg Decl. ¶ 29 (Ex.
`
`1303).)
`
`“Light source”
`
`A.
`The term “light source” appears in challenged claim 17. “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.” (Milchberg Decl. ¶ 30 (Ex. 1303).)
`
`9
`
`

`
`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`The ordinary and customary meaning of “light source”1 is a source of
`
`electromagnetic radiation in the extreme ultraviolet (10 nm to 100 nm), vacuum
`
`ultraviolet (100 nm to 200 nm), ultraviolet (200 nm to 400 nm), visible (400 to 700
`
`nm), near-infrared (700 nm to 1,000 nm (1 µm)), 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,” at 4 (2d ed. 2003) (“Silfvast”) (Ex. 1310).) The
`
`Patent Owner publishes a data sheet which is consistent with the ordinary and
`
`customary meaning, in considering EUV [Extreme Ultraviolet] to be within the
`
`meaning of “light source.” (See, e.g., EQ-10M Data Sheet (describing Energetiq’s
`
`EQ-10 product operating at 13.5 nm as an “EUV Light Source”) (Ex. 1311).)
`
`(Milchberg Decl. ¶ 31 (Ex. 1303).)
`
`The ’455 patent does not provide a definition of the term “light source” and
`
`uses the term consistent with the ordinary and customary meaning of the term. The
`
`’455 patent states that parameters such as the wavelength of the light from a light
`
`1 The term “light” is sometimes used more narrowly to refer only to visible light.
`
`However, references to “ultraviolet light” in the ’455 patent make clear that the
`
`broader meaning is intended because ultraviolet light has a wavelength shorter than
`
`that of visible light. (See, e.g., ʼ455 patent, 7:33-34; 8:44-45; 10:19-20; 10:48-50;
`
`12:3-5; 12:11-13; 12:44-46; 13:64-14:4; 14:55-57; 17:3-4 (Ex. 1301).) (See
`
`Milchberg Decl. ¶ 31 n.1 (Ex. 1303).)
`
`10
`
`

`
`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`source vary depending upon the application. (’455 patent, 1:25-27 (Ex. 1301).)
`
`The specification describes “ultraviolet light” as an example of the type of light
`
`that can be generated: “In some embodiments, the high brightness light 636
`
`includes ultraviolet light.” (’455 patent, 13:67-14:1 (Ex. 1301); see also id. at
`
`17:1-4 (discussing the ultraviolet light 836 generated by the plasma 832 of the light
`
`source).) (Milchberg Decl. ¶ 32 (Ex. 1303).)
`
`Therefore, the term “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.”2 (Milchberg Decl.
`
`¶ 33 (Ex. 1303).)
`
` “High brightness light”
`
`B.
`Challenged claim 17 recites the term “high brightness light.” For purposes
`
`
`2 The particular construction for the claim term “light source” was adopted by the
`
`Board in the Decision granting Institution of Inter Partes Review for claims 19 and
`
`39-41. (See Case No. IPR2015-01279, slip op. at 5 (PTAB Nov. 30, 2015) (Paper
`
`13).) This construction is equivalent to the Petitioner’s prior proposed construction
`
`for the term “light source” in the prior Petitions for the ’455 patent and other
`
`patents in the patent family. (Milchberg Decl. ¶ 33 n.2 (Ex. 1303).)
`
`11
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`

`
`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`of this proceeding, the term “high brightness light”3 should be construed to include
`
`“light sufficiently bright to be useful for: inspection, testing or measuring
`
`properties associated with semiconductor wafers or materials used in the
`
`fabrication of wafers, or as a source of illumination in a lithography system used in
`
`the fabrication of wafers, microscopy system, photoresist curing systems, or
`
`endoscopic tools.” (Milchberg Decl. ¶ 34 (Ex. 1303).)
`
`The ’455 patent defines “brightness”4 as “the power radiated by a source of
`
`light per unit surface area into a unit solid angle.” (’455 patent, 8:27-28 (Ex.
`
`3 For purposes of this proceeding, it is sufficient to interpret “high brightness light”
`
`as Petitioners explain above, and each prior art reference used in the grounds of
`
`unpatentability is directed to providing light with sufficient brightness for purposes
`
`identified in the challenged patent. Petitioners note that in an infringement
`
`proceeding in which the required brightness of the light were at issue, claims
`
`reciting “high brightness light” would be invalid under 35 U.S.C. § 112, second
`
`paragraph for indefiniteness because the patent does not specify how bright the
`
`light must be. (Milchberg Decl. ¶ 34 n.3 (Ex. 1303).)
`
`4 Although the ’455 patent uses the term “brightness,” “spectral brightness” is the
`
`more common term in optics and lasers. “Spectral brightness” refers to the optical
`
`power radiated per unit of wavelength (nm) per steradian, the unit of solid angle.
`
`(Milchberg Decl. ¶ 35 n.4 (Ex. 1303).)
`
`12
`
`

`
`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`1301).) The brightness of the light produced by a light source “determines” the
`
`ability of a system or operator to “see or measure things… with adequate
`
`resolution.” (’455 patent, 8:28-32 (Ex. 1301).) (Milchberg Decl. ¶ 35 (Ex. 1303).)
`
`The ’455 patent recognizes that high brightness light has been used for
`
`various purposes long before the ’455 patent was filed. The patent recognizes in
`
`the Background of the Invention that, “[f]or example, a high brightness light
`
`source can be used for inspection, testing or measuring properties associated with
`
`semiconductor wafers or materials used in the fabrication of wafers (e.g., reticles
`
`and photomasks).” (’455 patent, 1:17-21 (Ex. 1301).) It also identifies light
`
`sources that can be used “as a source of illumination in a lithography system used
`
`in the fabrication of wafers, a microscopy system[], or a photoresist curing system”
`
`as further examples of high brightness light sources. (’455 patent, 1:21-25 (Ex.
`
`1301).) Additionally, it describes and claims “a wafer inspection tool, a
`
`microscope, a metrology tool, a lithography tool, [and] an endoscopic tool” as tools
`
`for which the high brightness light is produced. (’455 patent, 2:46-50, 3:61-64,
`
`10:15-21, 15:8-14 (Ex. 1301).) More generally, the patent acknowledges that the
`
`brightness and other parameters of the light “vary depending upon the application.”
`
`(’455 patent, 1:25-27 (Ex. 1301).) (Milchberg Decl. ¶ 36 (Ex. 1303).)
`
`The Patent Owner has argued that the term “high brightness light” should be
`
`understood as “bright enough to be used for inspection, testing, or measuring
`
`13
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`

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`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`properties associated with semiconductor wafers or materials used in the
`
`fabrication of wafers, or in lithography systems used in the fabrication of wafers,
`
`microscopy systems, or photoresist curing systems—i.e., at least as bright as xenon
`
`or mercury arc lamps,” which is similar to the construction proposed below but
`
`omits applications specifically identified in the ’455 patent. (See Second
`
`Declaration of Donald K. Smith, Ph.D. in Support of Energetiq’s Reply Brief in
`
`Support of its Motion for Preliminary Injunction, dated March 17, 2015 ¶ 20
`
`(“Second Smith Decl.”) (Ex. 1308).) (Milchberg Decl. ¶ 37 (Ex. 1303).)
`
`Therefore, for purposes of this proceeding, the term “high brightness light”
`
`should be interpreted to include “light sufficiently bright to be useful for:
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`inspection, testing or measuring properties associated with semiconductor wafers
`
`or materials used in the fabrication of wafers, or as a source of illumination in a
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`lithography system used in the fabrication of wafers, microscopy systems,
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`photoresist curing systems, or endoscopic tools.” 5 (Milchberg Decl. ¶ 38 (Ex.
`
`1303).)
`
`
`5 The proposed construction for the claim term “high brightness light” was adopted
`
`by the Board in the Decision granting Institution of Inter Partes Review for claims
`
`19 and 39-41. (See Case No. IPR2015-01279 (PTAB Nov. 30, 2015) (Paper 13).)
`
`(Milchberg Decl. ¶ 38 n.5 (Ex. 1303).)
`
`14
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`

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`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`VII. THE CHALLENGED CLAIMS ARE INVALID
`A. Laser Sustained Plasma Light Sources Were Known Long Before
`the Priority Date of the ’455 Patent
`
`When the application that led to the ’455 patent was filed, there was nothing
`
`new about using an ignition source to generate a plasma in a chamber, a laser to
`
`sustain the plasma to produce high brightness light from the plasma, and reflective
`
`surfaces as described and claimed in the ’455 patent. This concept had been
`
`known and widely used since at least as early as the 1980s, more than two decades
`
`before the application date. For example, in 1983, Gärtner et al. filed a patent
`
`application entitled “Radiation source for optical devices, notably for
`
`photolithographic reproduction systems,” which published on May 3, 1985 as
`
`French Patent Application No. 2554302. (“Gärtner,” Ex. 1304.) As shown in Fig.
`
`1, reproduced below adjacent to Fig. 1 of the ’455 patent, Gärtner disclosed a light
`
`source with the same features claimed in the ’455 patent: (1) a chamber 1 (green);
`
`(2) an ignition source – pulsed laser 10 (blue), which ionizes a gas; (3) a laser to
`
`produce plasma light – laser 9 (red), which provides energy to the plasma 14 and
`
`produces light 15; and (4) a reflective surface 12 (purple). (Gärtner at 4:31-5:9
`
`(Ex. 1304).) Fig. 1 of the ’455 patent is also reproduced below. (Milchberg Decl.
`
`¶ 39 (Ex. 1303).)
`
`15
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`

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`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`
`’455 patent Fig. 1 (Ex. 1301) (Annotated)
`
`Gärtner, Fig. 1 (Ex. 1304)
`
`
`
`(Annotated)
`
`In addition, on August 31, 2005, Ershov et al. filed U.S. Patent Application
`
`No. 2006/0192152, entitled “LPP EUV Light Source Drive Laser System.”
`
`(“Ershov,” Ex. 1316). As shown in Figs. 1 and 12, reproduced below, Ershov
`
`discloses a light source with features similar to the ’455 patent: (1) a chamber
`
`(represented below in green); (2) an ignited plasma at focal point 28 (blue); (3) a
`
`laser for providing energy to the plasma – laser light 342 (red); and (4) reflective
`
`surface 30 for reflecting laser energy and plasma light (purple). (See Ershov ¶¶ 22-
`
`23, Fig. 1 (Ex. 1316).) (Milchberg Decl. ¶ 40 (Ex. 1303).)
`
`16
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`

`
`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`
`
`
`
`
`Ershov, Fig. 1 (Ex. 1316) (Annotated)
`
`
`
`Ershov, Fig. 12 (Ex. 1316) (Annotated)
`
`17
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`

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`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`B. Using a dichroic mirror to separate light of different wavelengths
`was well known in the art.
`
`Dichroic mirrors are standard optical elements that have been part of the
`
`skilled person’s toolkit for building optical systems for decades. (See, e.g., IEEE
`
`Standard Dictionary of Electrical and Electronic Terms (1988) (“Dichroic mirror
`
`(fiber optics). A mirror designed to reflect light selectively according to
`
`wavelength.”) (Ex. 1313).) Dichroic mirrors generally use the known principle of
`
`thin film interference, which uses alternating layers of optical coatings with
`
`different refractive indexes built upon a transparent substrate, such as glass or
`
`quartz. (See, e.g., Ingle, Crouch, “Spectrochemical Analysis,” Prentice Hall (1998)
`
`(“Another type of beam splitter is a wavelength-selective beam splitter or dichroic
`
`mirror. Such mirrors are made from multilayer, nonabsorbing films.”) (Ex.
`
`1315).) One of skill in the art would have known that by controlling the thickness
`
`and the number of layers, the frequency (wavelength) of the passband of the filter
`
`can be tuned and made as wide or narrow as desired. (Milchberg Decl. ¶ 41 (Ex.
`
`1303).)
`
`Furthermore, one of skill in the art would have understood how to use a
`
`dichroic mirror that selectively reflects at least one wavelength of light in order to
`
`separate out (i) light from a laser beam from (ii) light emitted by a target irradiated
`
`by the laser beam. For example, Ito describes using a dichroic mirror that reflects
`
`a laser beam having a fundamental frequency of 1064 nm onto a target, which
`
`18
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`

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`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`causes the target to generate light. (Ito at 3-4 (Ex. 1305).) The light generated
`
`from the target is then passed back to the dichroic mirror. Since the dichroic mirror
`
`only reflects light with wavelengths around 1064 nm, the generated light passes
`
`through the dichroic mirror without being reflected back toward the laser. (Id.)
`
`(Milchberg Decl. ¶ 42 (Ex. 1303).)
`
`Thus, the purportedly novel features of the ’455 patent are, in actuality,
`
`standard features of laser sustained plasma light sources described in prior art from
`
`the 1980s onward. (Milchberg Decl. ¶ 43 (Ex. 1303).)
`
`VIII. GROUNDS FOR FINDING THE CHALLENGED CLAIMS INVALID
`Pursuant to Rule 42.104(b)(4)-(5), specific grounds for finding the
`
`challenged claims invalid are identified below and discussed in the Milchberg
`
`Declaration (Ex. 1303). These grounds demonstrate in detail that claims 17 and 18
`
`are invalid under 35 U.S.C. § 103. (Milchberg Decl. § VII (Ex. 1303).)
`
`A. Ground 1: Claim 17 is unpatentable over Gärtner
`Claim 17 relates to a laser sustained plasma light source with a chamber
`
`containing a reflective surface. Claim 17 is obvious over Gärtner, as outlined in
`
`the chart below. (Milchberg Decl. ¶ 44 (Ex. 1303).)
`
`’455 Patent Claim 17
`
`Prior Art
`
`[17p] A light source, comprising:
`
`Gärtner at 1:1-4, Figs. 1-4
`
`19
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`

`
`U.S. Patent 7,786,455
`Petition for Inter Partes Review
`
`’455 Patent Claim 17
`
`Prior Art
`
`[17a] a chamber comprising a reflective surface; Gärtner at 3:20, 4:32, 5:3-5;
`5:15-16, 5:26-6:2, 6:9-10, Figs.
`1-4
`
`[17b] an ignition source for ionizing a gas within
`the chamber;
`
`Gärtner at 1:22, 3:20, 4:32, 5:5-
`8, 5:15-16, 6:9-10, Figs. 1-4
`
`[17c] at least one laser external to the chamber
`for providing electromagnetic energy to the
`ionized gas within the chamber to produce a
`plasma that generates a high brightness light; and
`
`Gärtner at 1:1-4, 3:1, 3:22-24,
`5:5-9, Figs. 1-4
`
`[17d] a reflector positioned along a path that the
`electromagnetic energy travels from the at least
`one laser to the reflective surface of the chamber.
`
`Gärtner at 3:29-32, 4:5-12, 5:8-
`9, 5:34-6:2, 6:9-16, 6:10-12,
`Figs. 1-4
`
`(a) Gärtner is prior art that was not considered by the Patent Office
`during examination.
`
`Gärtner is prior art under 35 U.S.C. § 102(b) because it published more than
`
`a year before the earliest claimed priority date for the ’455 patent, which is March
`
`31, 2006. Gärtner was not considered by the Examiner during prosecution of the
`
`’455 patent. (Milchberg Decl. ¶ 45 (Ex. 1303).)
`
`(b) Claim 17 is Obvious over Gärtner
`
`a)
`
`Claim 17 - Preamble (element [17p])
`
`The Preamble of claim 17 recites “[a] light source.” (’455 Patent, 18:47 (Ex.
`
`1301