`____________________________________________
`
`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 IPR2016-00578
`
`
`
`DECLARATION OF HOWARD MILCHBERG, PH.D.
`REGARDING U.S. PATENT NO. 7,786,455
`CLAIMS 20, 21, 24
`
`ASML 1403
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`
`
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`
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`TABLE OF CONTENTS
`
`
`B.
`
`V.
`
`I.
`BACKGROUND ............................................................................................. 1
`LEGAL PRINCIPLES ..................................................................................... 4
`II.
`PERSON OF ORDINARY SKILL IN THE ART .......................................... 5
`III.
`IV. OVERVIEW OF THE ’455 PATENT ............................................................ 6
`A.
`Summary of the Prosecution History .................................................... 8
`CLAIM CONSTRUCTION ............................................................................ 9
`A.
`“High brightness light” .......................................................................... 9
`B.
`“Large solid angle” .............................................................................. 12
`VI. THE CHALLENGED CLAIMS ARE INVALID ......................................... 13
`A.
`Laser Sustained Plasma Light Sources Were Known Long
`Before the Priority Date of the ’455 Patent ......................................... 13
`Using a dichroic mirror to separate light of different
`wavelengths was well known in the art. .............................................. 16
`VII. GROUNDS FOR FINDING THE CHALLENGED CLAIMS INVALID ... 17
`A. Ground 1: Claim 20 is unpatentable over Gärtner in view of
`Ershov .................................................................................................. 17
`(a) Gärtner and Ershov are each prior art that was not considered by
`the Patent Office during examination ........................................... 18
`(b) Claim 20 is obvious by Gärtner in view of Ershov ...................... 20
`Ground 2: Claim 21 is unpatentable over Gärtner in view of
`Ershov and further in view of Ito ........................................................ 31
`(a) Gärtner, Ershov and Ito are each prior art that was not considered
`by the Patent Office during examination. ..................................... 31
`(b) Claim 21 ....................................................................................... 32
`Ground 3: Claim 24 is unpatentable over Gärtner in view of
`Silverman ............................................................................................. 41
`(a) Gärtner and Silverman are each prior art that was not considered
`by the Patent Office during examination. ..................................... 41
`(b) Claim 24 ....................................................................................... 41
`(c) Reasons to combine ...................................................................... 46
`
`B.
`
`C.
`
`i
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`VIII. RESPONSE TO ARGUMENTS RAISED BY PATENT OWNER IN ITS
`PRELIMINARY INJUNCTION MOTION .................................................. 48
`A.
`Patent Owner’s Arguments Regarding the Content of the Prior
`Art ........................................................................................................ 49
`(a) High Brightness Light .................................................................. 49
`Patent Owner’s Arguments Regarding Objective Indicia of
`Non-Obviousness ................................................................................ 53
`IX. AVAILABILITY FOR CROSS-EXAMINATION ...................................... 54
`X.
`RIGHT TO SUPPLEMENT .......................................................................... 55
`XI.
`JURAT ........................................................................................................... 56
`
`
`
`B.
`
`ii
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`
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`I, Howard Milchberg, Ph.D., declare as follows:
`
`1. My name is Howard Milchberg.
`
`I.
`
`BACKGROUND
`2.
`
`I am a Professor of Physics and Electrical and Computer Engineering
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`at the University of Maryland in College Park, Maryland.
`
`3.
`
`I received a B.Eng. in Engineering Physics from McMaster University
`
`in Hamilton, Ontario, Canada in 1979. I received a Ph.D. in Astrophysical
`
`Sciences from Princeton University in Princeton, New Jersey in 1985.
`
`4.
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`After receiving my doctorate, I worked at AT&T Bell Laboratories in
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`as a postdoc from 1985 to 1987.
`
`5.
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`In 1988, I was appointed Assistant Professor in the Department of
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`Electrical and Computer Engineering at the University of Maryland. In 1993, I
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`became Associate Professor in this same department, and in 1995, I became
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`Professor in this department. I am currently Professor in the Departments of
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`Physics and Electrical and Computer Engineering.
`
`6.
`
`Since joining the faculty of the University of Maryland in 1988, I
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`have been engaged in research in: nonlinear optics; laser and optical physics; the
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`interaction of intense electromagnetic fields with atoms, ions, gases, solids, and
`
`plasmas; the generation and application of coherent and incoherent short
`
`wavelength radiation; and laser-based acceleration of charged particles. My
`
`1
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`research has been featured in Physical Review Letters, Optics Letters, Optics
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`Express, Physical Review X; Optica; Physics of Plasmas; Applied Physics Letters,
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`and the Journal of the Optical Society of America, and has received popular press
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`coverage in the Washington Post, Le Monde, Science News, Physics Today,
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`Nature, Smithsonian Magazine, and Gizmodo, among others.
`
`7.
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`I taught/teach courses in electromagnetic theory, quantum mechanics,
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`laser science, and laser-plasma interactions among others. I have directed the
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`dissertations of 17 individuals who received the Ph.D. degree in Physics or
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`Electrical and Computer Engineering.
`
`8.
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`I have authored or co-authored over 120 peer-reviewed academic
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`publications in the fields of physics and applied physics.
`
`9.
`
`From 1979 through 1984, I was a NSERC Postgraduate Fellow
`
`through the National Research Council Canada. From 1988 through 1993, I was a
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`National Science Foundation Presidential Young Investigator. I am fellow of the
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`American Physical Society and the Optical Society of America. In 2005, I
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`received the University of Maryland Distinguished Scholar-Teacher award. In
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`2005, I also received the American Physical Society Award for Excellence in
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`Plasma Physics Research.
`
`10.
`
`I am a named inventor on one United States patent and have patent
`
`applications pending both in the United States and abroad.
`
`2
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`11. A copy of my curriculum vitae is attached as Appendix A.
`
`12.
`
`I have reviewed the specification and claims of U.S. Patent No.
`
`7,786,455 (“the ’455 patent,” Ex. 1401). I have been informed that the ’455 patent
`
`claims priority to U.S. Application No. 11/395,523, filed on March 31, 2006, now
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`U.S. Patent No. 7,435,982 (the “’982 patent”).
`
`13.
`
`I have also reviewed the following references, all of which I
`
`understand to be prior art to the ’455 patent:
`
` French Patent Publication No. FR2554302A1 (with English
`Translation), published May 3, 1985 (“Gärtner,” Ex. 1404).
`
` Japanese Patent Publication No. JPH04-144053A, (with English
`Translation), published May 18, 1992 (“Ito,” Ex. 1405).
`
` U.S. Patent Publication No. 2006/0192152, filed August 31, 2005,
`published August 31, 2006 (“Ershov,” Ex. 1416).
`
` U.S. Patent Publication No. 2004/0183031, filed March 20, 2003,
`published September 23, 2004 (“Silverman,” Ex. 1415).
`
`14.
`
`I have also reviewed the exhibits cited in this Declaration, as well as
`
`
`
`
`
`
`
`
`
`the Declaration of Dr. Eden in support of an IPR petition directed to the same
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`patent. (Case No. IPR2015-01279 (Exhibit 1003).)
`
`15.
`
`I am being compensated at my normal consulting rate for my work.
`
`16. My compensation is not dependent on and in no way affects the
`
`substance of my statements in this Declaration.
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`3
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`I have no financial interest in the Petitioners. I similarly have no
`
`17.
`
`financial interest in the ’455 patent.
`
`II. LEGAL PRINCIPLES
`18.
`I have been informed that a claim is invalid as anticipated under 35
`
`U.S.C. § 102(a) if “the invention was known or used by others in this country, or
`
`patented or described in a printed publication in this or a foreign country, before
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`the invention thereof by the applicant for patent.” I have also been informed that a
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`claim is invalid as anticipated under 35 U.S.C. § 102(b) if “the invention was
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`patented or described in a printed publication in this or a foreign country or in
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`public use or on sale in this country, more than one year prior to the date of the
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`application for patent in the United States.” Further I have been informed that a
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`claim is invalid as anticipated under 35 U.S.C. § 102(e) if “the invention was
`
`described in … an application for patent, published under section 122(b), by
`
`another filed in the United States before the invention by the applicant for patent.”
`
`It is my understanding that for a claim to be anticipated, all of the limitations must
`
`be present in a single prior art reference, either expressly or inherently.
`
`19.
`
`I have been informed that a claim is invalid as obvious under 35
`
`U.S.C. § 103(a):
`
`
`
`if the differences between the subject matter sought to be patented and
`the prior art are such that the subject matter as a whole would have
`
`4
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`been obvious at the time the invention was made to a person having
`ordinary skill in the art to which [the] subject matter pertains.
`
`20.
`
`I understand that a claimed invention would have been obvious, and
`
`therefore not patentable, if the subject matter claimed would have been considered
`
`obvious to a person of ordinary skill in the art at the time that the invention was
`
`made. I understand that when there are known elements that perform in known
`
`ways and produce predictable results, the combination of those elements is likely
`
`obvious. Further, I understand that when there is a predictable variation and a
`
`person would see the benefit of making that variation, implementing that
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`predictable variation is likely not patentable. I have also been informed that
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`obviousness does not require absolute predictability of success, but that what does
`
`matter is whether the prior art gives direction as to what parameters are critical and
`
`which of many possible choices may be successful.
`
`III. PERSON OF ORDINARY SKILL IN THE ART
`21. 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
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`master’s degree in physics, electrical engineering, or an equivalent field and 4-5
`
`years of work experience with lasers and plasma.
`
`5
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`IV. OVERVIEW OF THE ’455 PATENT
`22. The ’455 patent is directed to a laser sustained plasma light source for
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`use in, 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, 4:25-7:34 (Ex. 1401).)
`
`
`
`’455 patent Fig. 1 (Ex. 1401) (Annotated)
`
`23. The ’455 patent also describes the use of reflectors for reflecting or
`
`transmitting plasma light and laser energy. For example, as illustrated in Figure 5,
`
`below, reflective surface 540 (purple) can direct laser energy to the plasma in the
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`chamber and direct emitted light towards the output. (’455 patent, 13:10-29 (Ex.
`
`1401).) Additionally, reflector 512 (orange) reflects the laser beam 520 toward the
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`reflective surface 540 (purple) of the chamber and the reflector 512 (orange) is
`
`substantially transparent to plasma light 536. (’455 patent, 13:10-29 (Ex. 1401).)
`
`6
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
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`’455 patent Fig. 5 (Ex. 1401) (Annotated)
`
`
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`24. According to the ’455 patent, prior art light sources relied upon
`
`electrodes to both generate and sustain the plasma, which resulted in wear and
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`contamination. (’455 patent, 1:28-44 (Ex. 1401).) 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. 1401).) 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. 1401).) Additionally, the
`
`purported invention also involves different configurations of reflectors to direct
`
`energy and light. (’455 patent, 4:25-7:34 (Ex. 1401).)
`
`25. As discussed below, sustaining a plasma with a laser to produce high
`
`brightness light and using configurations of reflectors to direct energy and light
`
`was well known prior to the earliest claimed priority date of the ’455 patent. Prior
`
`art references, such as Gärtner, disclosed a laser-sustained plasma light source with
`
`7
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`the same elements as the ’455 patent: a chamber, an ignited plasma, a laser, and
`
`reflective surfaces.
`
`26. Furthermore, there was nothing new about using a dichroic mirror to
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`separate out (a) light from a laser beam, and (b) light emitted from a target
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`irradiated by the laser. For example, Ito disclosed using a dichroic mirror to
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`separate out light in this fashion.
`
`A.
`
`Summary of the Prosecution History
`
`27. 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
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`chamber with a reflective surface and providing laser energy to the ionized gas in
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`the chamber to produce a plasma that generates high brightness light. (Notice of
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`Allowability, dated May 4, 2010, at 3-4 (Ex. 1406).) The ’455 patent issued on
`
`August 31, 2010.
`
`28. 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. 30, 2015) (Paper 13).)
`
`8
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`
`V. CLAIM CONSTRUCTION
`29.
`I have applied the “broadest reasonable interpretation” standard in
`
`proposing the claim constructions below. However, based on my reading of the
`
`’455 patent’s specification and the ordinary meanings of the claim terms, the prior
`
`art teaches each claim limitation under any reasonable interpretation of the claim
`
`terms. My analysis is not dependent on application of the “broadest reasonable
`
`interpretation” standard.
`
`A.
`“High brightness light”
`30. The term “high brightness light”1 is recited in claims 19 (from which
`
`the challenged claims depend), 21, and 24. For purposes of this proceeding, the
`
`
`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;
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`12:3-5, 12:11-13, 12:44-46, 13:64-14:4, 14:55-57, 17:3-4 (Ex. 1401).)
`
`9
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`term “high brightness light”2 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,
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`microscopy system, photoresist curing systems, or endoscopic tools.”
`
`31. The ’455 patent defines “brightness”3 as “the power radiated by a
`
`source of light per unit surface area into a unit solid angle.” (’455 patent, 8:27-28
`
`(Ex. 1401).) 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. 1401).)
`
`32. The ’455 patent recognizes that high brightness light has been used
`
`for various purposes long before the ’455 patent was filed. The patent recognizes
`
`2 The ’455 patent does not specify how bright the light must be. However, for
`
`purposes of this proceeding, it is sufficient to interpret “high brightness light” as
`
`explained 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.
`
`3 Although the ’455 patent uses the term “brightness,” “spectral brightness” is the
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`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.
`
`10
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`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. 1401).) It also identifies light
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`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”
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`as further examples of high brightness light sources. (’455 patent, 1:21-25 (Ex.
`
`1401).) Additionally, it describes and claims “a wafer inspection tool, a
`
`microscope, a metrology tool, a lithography tool, [and] an endoscopic tool” as tools
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`for which the high brightness light is produced. (’455 patent, 2:46-50, 3:61-64,
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`10:15-21, 15:8-14 (Ex. 1401).) More generally, the patent acknowledges that the
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`brightness and other parameters of the light “vary depending upon the application.”
`
`(’455 patent, 1:25-27 (Ex. 1401).)
`
`33. 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 properties associated with semiconductor wafers or materials used in
`
`the fabrication of wafers, or in lithography systems used in the fabrication of
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`wafers, microscopy systems, or photoresist curing systems—i.e., at least as bright
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`as xenon or mercury arc lamps,” which is similar to the construction proposed
`
`11
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`below but omits applications specifically identified in the ’455 patent. (See Second
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`Smith Declaration ¶ 20 (Ex. 1408).)
`
`34. Therefore, for purposes of this proceeding, the term “high brightness
`
`light” should be interpreted 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
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`lithography system used in the fabrication of wafers, microscopy systems,
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`photoresist curing systems, or endoscopic tools.” 4
`
`B.
`“Large solid angle”
`35. The term “large solid angle” is recited in claim 24. For purposes of
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`this proceeding, the term “large solid angle”5 should be construed to mean a solid
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`angle greater than 3 steradians. Like claim 24 of the ’455 patent, claim 12 recites a
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`“reflective surface of the chamber is adapted to collect the high brightness light
`
`generated by the plasma over a large solid angle.” (’455 patent, 18:34-36, 19:21-
`
`4 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
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`19 and 39-41. (See Case No. IPR2015-01279 (PTAB Nov. 30, 2015) (Paper 13).)
`
`5 The ’455 patent does not specify how large the solid angle must be. However,
`
`for purposes of this proceeding, it is sufficient to interpret “large solid angle” as
`
`explained above.
`
`12
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`23 (Ex. 1401).) Claims 13 and 14, which depend from claim 12, recite that the
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`large solid angle “is greater than about 3 steradians” and “is about 5 steradians.”
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`(’455 patent, 18:37-40 (Ex. 1401).) The ’455 patent provides no further insight
`
`into what constitutes a “large” solid angle. It provides in the specification
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`examples of solid angles of 0.012 and 0.048 steradians (’455 patent, 16:65-17:27
`
`(Ex. 1401).), as well as of “larger” solid angles of 5 and 6.28 steradians (’455
`
`patent, 17:28-42 (Ex. 1401).) Therefore, the term “large solid angle” should be
`
`construed to mean a solid angle greater than 3 steradians.
`
`VI. THE CHALLENGED CLAIMS ARE INVALID
`A. Laser Sustained Plasma Light Sources Were Known Long Before
`the Priority Date of the ’455 Patent
`36. 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. 1404.) As shown in Fig.
`
`1, reproduced below adjacent to Fig. 1 of the ’455 patent, Gärtner disclosed a light
`
`13
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`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). Fig. 1 of the ’455 patent
`
`is also reproduced below. (Gärtner, 4:31-5:9 (Ex. 1404).)
`
`’455 patent Fig. 1 (Ex. 1401) (Annotated)
`
`Gärtner, Fig. 1 (Ex. 1404)
`
`
`
`(Annotated)
`
`37.
`
`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. 1416). 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)
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`reflective surface 30 for reflecting plasma light and laser energy (purple). (See
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`Ershov, ¶¶ 22-23, Fig. 1 (Ex. 1416).)
`
`14
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`
`Ershov, Fig. 1 (Ex. 1416) (Annotated)
`
`
`
`
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`
`
`Ershov, Fig. 12 (Ex. 1416) (Annotated)
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`15
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`B. Using a dichroic mirror to separate light of different wavelengths
`was well known in the art.
`38. 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. 1410).) Dichroic mirrors generally use the known principle of
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`thin film interference, which uses alternating layers of optical coatings with
`
`different refractive indexes built upon a transparent substrate, such as glass or
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`quartz. (See, e.g., James Ingle and Stanley Crouch, “Spectrochemical Analysis,” at
`
`59 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. 1411).) 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.
`
`39. 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
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`irradiated by the laser beam. For example Ito describes using a dichroic mirror that
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`reflects a laser beam having a fundamental frequency of 1064 nm onto a target,
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`which causes the target to generate light. (Ito at 3 (Ex. 1405).) The light generated
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`16
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`from the target is then passed back to the dichroic mirror. Since the dichroic
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`mirror in this example only reflects light with wavelengths around 1064 nm, the
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`generated light passes through the dichroic mirror without being reflected back
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`toward the laser.
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`40. Thus, the purportedly novel features of the ’455 patent are, in
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`actuality, standard features of laser sustained plasma light sources described in
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`prior art from the 1980s onward.
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`VII. GROUNDS FOR FINDING THE CHALLENGED CLAIMS INVALID
`41. Pursuant to Rule 42.104(b)(4)-(5), specific grounds for finding the
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`challenged claims invalid are identified below. These grounds demonstrate in
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`detail that claims 20, 21, and 24 are obvious.
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`A. Ground 1: Claim 20 is unpatentable over Gärtner in view of
`Ershov
`42. Claim 20 relates to a method for producing light by ionizing a gas
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`within a chamber comprising a reflective surface and by producing a plasma that
`
`generates a high brightness light. Claim 20 is obvious over Gärtner in view of
`
`Ershov, as outlined in the chart below.
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`’455 Patent Claim 20
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`Prior Art
`
`[19p] A method of producing light, comprising:
`
`Gärtner, 1:1-4, Figs. 1-4
`
`[19a] ionizing with an ignition source a gas within
`a chamber comprising a reflective surface; and
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`Gärtner, 3:20, 4:32, 5:15-16,
`6:9-10, Figs. 1-4
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`17
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`
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`’455 Patent Claim 20
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`Prior Art
`
`Gärtner, 1:1-2, 3:22-24, 5:5-9,
`Figs. 1-4
`
`Ershov, ¶ 0051, Fig. 12
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`[19b] providing laser energy to the ionized gas in
`the chamber to produce a plasma that generates a
`high brightness light.
`
`[20] The method of claim 19, comprising directing
`the laser energy comprising a first set of
`wavelengths of electromagnetic energy toward the
`reflector, the reflector reflects at least a portion of
`the first wavelengths of electromagnetic energy
`toward the reflective surface of the chamber, the
`reflective surface directs a portion of the first set of
`wavelengths of electromagnetic energy toward the
`plasma.
`
`(a) Gärtner and Ershov are each prior art that was not considered by
`the Patent Office during examination
`
`43.
`
`I have been informed that Gärtner is prior art under 35 U.S.C. §
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`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.
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`I have been informed that Ershov is prior art under 35 U.S.C. §§
`
`44.
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`102(a)6 and/or 102(e)7 because it was filed August 31, 2005 and published August
`
`6 The reflector and reflective surface claimed in challenged claims 20-21 of the
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`’455 patent was first arguably disclosed in the ’455 patent. (See, e.g., ʼ455 patent,
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`13:10-29 (Ex. 1401).) The “reflector reflects at least a portion of the first
`
`wavelengths of electromagnetic energy toward the reflective surface of the
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`chamber, [and] the reflective surface directs a portion of the first set of
`
`wavelengths of electromagnetic energy toward the plasma” does not appear at all
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`in the ʼ982 patent, the parent of the ʼ455 patent. (See generally ʼ982 patent (Ex.
`
`1413).) Thus, challenged claims 20-21 of the ’455 patent can only properly
`
`establish a priority date to the ’455 patent filing date of April 2, 2007. Because
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`Ershov was published before April 2, 2007, I have been informed it is therefore
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`prior art under 35 U.S.C. § 102(a) to challenged claims 20-21.
`
`7 The portions of Ershov relied upon in this Petition are supported by Ershov’s
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`parent application, U.S. Patent Application No. 11/174,299 (“the ʼ299
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`application”), which was filed on June 29, 2005 (Ex. 1414). See, e.g., ʼ299
`
`application, 15:3-16 (corresponding to Ershov, ¶ [0051]), 1:16-17 (corresponding
`
`to Ershov, ¶ [0002]), 10:26-11:20 (corresponding to Ershov, ¶ [0041]), 5:19-6:8
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`(corresponding to Ershov, ¶ [0023]) (Ex. 1414). Accordingly, Ershov is entitled to
`
`a prior art date of June 29, 2005.
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`19
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`U.S. Patent 7,786,455
`Declaration of Howard Milchberg, Ph.D.
`31, 2006. Ershov was not considered by the Examiner during prosecution of the
`
`’455 patent.
`
`(b) Claim 20 is obvious by Gärtner in view of Ershov
`
`45. Claim 20 of the ’455 patent, which depends from independent claim
`
`19, is rendered obvious by Gärtner in view of Ershov.
`
`a)
`
`Claim 19 - Preamble (element [19p])
`
`46. The Preamble of claim 19 recites “A method of producing light.”
`
`(’455 patent, 18:63 (Ex. 1401).) Gärtner discloses the preamble. For example,
`
`Gärtner discloses a “radiation source for optical devices,” which is a light source.
`
`(Gärtner, 1:1, Figs. 1-4 (Ex. 1404).) Gärtner’s light source can be used for
`
`applications like “illuminating a photoresist.” (Gärtner, 1:4 (Ex. 1404).)
`
`b)
`
`Claim 19 - Chamber and Ignition Source (element [19a])
`
`47. Claim 19 recites “ionizing with an ignition source a gas within a
`
`chamber comprising a reflective surface.” (’455 patent, 18:64-65 (Ex. 1401).)
`
`Gärtner discloses this limitation.
`
`48. For example, Gärtner discloses a “chamber.” (Gärtner, 3:20, 6:9,
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`Figs. 1-4 (disclosing “gas-tight chamber ”); 5:27-28, Fig. 2 (“A casing 16, the
`
`concave mirror 17 and the quartz window 18 constitute the gas-tight chamber
`
`containing the discharge medium 19.”); 6:9, Figs. 3-4 (“discharge chambers 35 and
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`36”) (Ex. 1404); see also ’455 patent, 1:30-32 (admitting light source chambers
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`were known in the art) (Ex. 1401).) Gärtner’s gas-tight chamber contains a
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`20
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`Declaration of Howard Milchberg, Ph.D.
`“discharge medium” such as “argon or xenon” (ionized gas). (Gärtner, 4:32, 5:15-
`
`16 (Ex. 1404).)
`
`49. Gärtner’s chamber comprises a reflective surface. (Gärtner, 5:3-5,
`
`Fig. 1 (disclosing “concave mirror 12 mounted on the wall of the chamber.”); 5:26-
`
`6:2, Fig. 2 (disclosing “concave mirror 17”); 6:9-10, Figs. 3, 4 (“Figs. 3 and 4
`
`show embodiments wherein the discharge chambers 35 and 36 are constituted by
`
`ellipsoid reflectors”) (Ex. 1404).)
`
`50. Gärtner’s “laser 10” is an ignition source. (Gärtner, 5:5-8 (Ex. 1404).)
`
`In particular, laser 10 is “a nitrogen pulse laser” that “produces an electrical
`
`discharge” in the medium to create “absorbent plasma 14.” (Gärtner, 5:5-8 (Ex.
`
`1404).) Gärtner further discloses electrodes as ignition sources. (Gärtner, 1