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 IPR2015-01368
`
`
`DECLARATION OF J. GARY EDEN, PH.D.
`U.S. PATENT NO. 8,525,138
`CLAIMS 1-5
`
`
`
`
`
`
`
`
`
`ASML 1003
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`TABLE OF CONTENTS
`
`Page
`
`V. 
`
`BACKGROUND ............................................................................................. 1 
`I. 
`LEGAL PRINCIPLES ..................................................................................... 6 
`II. 
`PERSON OF ORDINARY SKILL IN THE ART .......................................... 7 
`III. 
`IV.  OVERVIEW OF THE ’138 PATENT ............................................................ 8 
`A. 
`Summary of the Prosecution History .................................................. 11 
`CLAIM CONSTRUCTION .......................................................................... 14 
`A. 
`“Light source” ..................................................................................... 14 
`VI.  THE CHALLENGED CLAIMS ARE INVALID ......................................... 16 
`A. 
`Laser-Sustained Light Sources Were Known Long Before the
`Priority Date of the ’138 Patent........................................................... 16 
`Sustaining a plasma with a laser operating within 10 nm of a
`strong absorption line was well known in the art. ............................... 18 
`VII.  GROUNDS FOR FINDING THE CHALLENGED CLAIMS INVALID ... 24 
`A.  Ground 1: Claims 1-5 Are Unpatentable Over Gärtner in View
`of Beterov ............................................................................................ 24 
`(a)  Gärtner and Beterov are each prior art that was not considered by
`the Patent Office during examination. .......................................... 25 
`(b)  Overview of Gärtner ..................................................................... 25 
`(c)  Overview of Beterov .................................................................... 28 
`(d)  Independent Claim 1 is Unpatentable Over Gärtner in View of
`Beterov ......................................................................................... 33 
`(e)  Dependent Claims 2-5 are Unpatentable over Gärtner in view of
`Beterov ......................................................................................... 44 
`Ground 2: Claims 1-5 Are Unpatentable Over Gärtner in View
`of Wolfram .......................................................................................... 46 
`(a)  Gärtner and Wolfram are each prior art that was not considered
`by the Patent Office during examination. ..................................... 46 
`(b)  Independent Claim 1 is Unpatentable Over Gärtner in View of
`Wolfram ........................................................................................ 47 
`
`B. 
`
`B. 
`
`i
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`(c)  Dependent Claims 2-5 are Unpatentable over Gärtner in view of
`Wolfram ........................................................................................ 53 
`VIII.  RESPONSE TO ARGUMENTS RAISED BY PATENT OWNER IN ITS
`PRELIMINARY injunction motion .............................................................. 54 
`A. 
`Patent Owner’s Arguments Regarding the Content of the Prior
`Art ........................................................................................................ 54 
`Patent Owner’s Arguments Regarding Objective Indicia of
`Non-Obviousness ................................................................................ 55 
`IX.  AVAILABILITY FOR CROSS-EXAMINATION ...................................... 57 
`X. 
`RIGHT TO SUPPLEMENT .......................................................................... 57 
`XI. 
`JURAT ........................................................................................................... 58 
`
`B. 
`
`ii
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`I, J. Gary Eden, Ph.D., declare as follows:
`
`1. My name is J. Gary Eden.
`
`I.
`
`BACKGROUND
`2.
`
`I am the Gilmore Family Professor of Electrical and Computer
`
`Engineering and Director of the Laboratory for Optical Physics and Engineering at
`
`the University of Illinois in Urbana, Illinois.
`
`3.
`
`I received a B.S. in Electrical Engineering (High Honors) from the
`
`University of Maryland, College Park in 1972 and an M.S. and Ph.D. in Electrical
`
`Engineering from the University of Illinois in 1973 and 1976, respectively.
`
`4.
`
`After receiving my doctorate, I served as a National Research Council
`
`Postdoctoral Research Associate at the United States Naval Research Laboratory
`
`(“NRL”), Optical Sciences Division, in Washington, DC from 1975 to 1976. As a
`
`research physicist in the Laser Physics Branch (Optical Sciences Division) from
`
`1976 to 1979, I made several contributions to the visible and ultraviolet lasers and
`
`laser spectroscopy field, including the co-discovery of the KrCl rare gas-halide
`
`excimer laser and the proton beam pumped laser (Ar-N2, XeF). In 1979, I received
`
`a Research Publication Award for my work at the NRL.
`
`5.
`
`In 1979, I was appointed assistant professor in the Department of
`
`Electrical and Computer Engineering at the University of Illinois. In 1981, I
`
`became associate professor in this same department, and in 1983, I became
`
`1
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`professor in this department. In 1985, I was named the Director of the Laboratory
`
`for Optical Physics and Engineering, and in 2007, I was named the Gilmore Family
`
`Professor of Electrical and Computer Engineering. I continue to hold both
`
`positions today. In addition, I am also Research Professor in the Coordinated
`
`Science Laboratory and the Micro and Nanotechnology Laboratory.
`
`6.
`
`Since joining the faculty of the University of Illinois in 1979, I have
`
`been engaged in research in atomic, molecular and ultrafast laser spectroscopy, the
`
`discovery and development of visible and ultraviolet lasers, and the science and
`
`technology of microcavity plasma devices. My research has been featured in Laser
`
`Focus, Photonics Spectra, Electronics Weekly (UK), the Bulletin of the Materials
`
`Research Society, Microwaves, Optical Spectra, Electro-Optical Systems Design,
`
`Optics and Laser Technology, Electronics, Optics News, Lasers and Optronics,
`
`IEEE Potentials, IEEE Spectrum, and IEEE Circuits and Devices. My work was
`
`highlighted in the National Academy of Sciences report Plasma 2010, published in
`
`2007.
`
`7.
`
`I have made several major contributions to the field of laser physics,
`
`plasma physics, and atomic and molecular physics. I co-invented a new form of
`
`lighting, “light tiles”, that are thin and flat. This culminated in the formation of a
`
`company known as Eden Park Illumination. I discovered numerous ultraviolet,
`
`visible and near-infrared atomic and molecular lasers, including the KrCl
`
`2
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`ultraviolet (excimer) laser, the optically-pumped XeF, HgCl, and rare gas lasers
`
`and the CdI, CdBr, ZnI, Li, Fe, and Cd visible and near-infrared lasers. I
`
`demonstrated the first long pulse (> 1 µs) excimer laser and the first lasers (Ar –
`
`N2, XeF) pumped by a proton beam. The excimer lasers are now used worldwide
`
`in photolithography, surgical procedures (such as corneal refractive correction) and
`
`micromachining of materials. I discovered the laser excitation spectroscopy of
`
`photoassociation (the absorption of optical radiation by free atomic pairs) of
`
`thermal atoms as a probe of the structure of transient molecules. I demonstrated
`
`with my graduate students the first ultraviolet and violet glass fiber lasers. I
`
`discovered the excimer-pumped atomic lasers (lasing on the D1 and D2 lines of Na,
`
`Cs, and Rb) for laser guide stars and mesosphere probing by LIDAR. I conducted
`
`the first observation (by laser spectroscopy) of Rydberg series for the rare gas
`
`diatomics (Ne2, Ar2, Kr2, Xe2) and the first measurement of the rotational constants
`
`for Ne2 and Ar2, as well as the vibrational constants for Ne2+. I pioneered the
`
`development of microcavity plasma devices and arrays in silicon, Al/Al2O3, glass,
`
`ceramics, and multilayer metal/polymer structures. For this, I was the recipient of
`
`the C.E.K. Mees Award from Optical Society of America, the Aaron Kressel
`
`Award from the Photonics Society of the IEEE, and the Harold E. Edgerton Award
`
`from the International Society for Optical Engineering. I was the Fulbright-Israel
`
`Distinguished Chair in the Physical Sciences and Engineering from 2007 to 2008.
`
`3
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`I am a Fellow of the American Physical Society, the Optical Society of America,
`
`the Institute of Electrical and Electronics Engineers, the American Association for
`
`the Advancement of Science (AAAS), and the SPIE (International Society for
`
`Optical Engineering).
`
`8.
`
`I taught/teach courses in laser physics, electromagnetics (including
`
`optics, optical waveguides, antennas), plasma physics, semiconductor electronic
`
`devices, electromagnetics, and analog signal processing, among others. I have
`
`directed the dissertations of 46 individuals who received the Ph.D. degree in
`
`Physics, Electrical and Computer Engineering, or Materials Science and
`
`Engineering.
`
`9.
`
`I have also served as Assistant Dean in the College of Engineering,
`
`Associate Dean of the Graduate College, and Associate Vice-Chancellor for
`
`Research.
`
`10.
`
`I have authored or co-authored over 280 peer-reviewed academic
`
`publications in the fields of laser physics, plasma physics, atomic and molecular
`
`physics, and quantum electronics. I have served as Editor-in-Chief of the IEEE
`
`Journal of Quantum Electronics and am currently Editor-in-Chief of Progress in
`
`Quantum Electronics and Associate Editor of Applied Physics Reviews.
`
`11.
`
`I am currently a member of four honorary organizations. In 1998, I
`
`served as President of the IEEE Lasers and Electro-Optics Society (LEOS),
`
`4
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`following earlier service as a member of the LEOS Board of Governors, and as the
`
`Vice-President for Technical Affairs.
`
`12. From 1996 through 1999, I was the James F. Towey University
`
`Scholar at the University of Illinois. I received the LEOS Distinguished Service
`
`Award, was awarded the IEEE Third Millennium Medal in 2000 and was named a
`
`LEOS Distinguished Lecturer for 2003-2005.
`
`13.
`
`I am a co-founder of Eden Park Illumination (2007) and EP
`
`Purification (2010).
`
`14.
`
`In 2014, I was elected into the National Academy of Engineering, and
`
`the National Academy of Inventors.
`
`15.
`
`I am a named inventor on over seventy (73) United States and
`
`international patents and have patent applications pending both in the United States
`
`and abroad.
`
`16. A copy of my curriculum vitae is attached as Appendix A.
`
`17.
`
`I have reviewed the specification and claims of U.S. Patent No.
`
`8,525,138 (the “’138 patent”; Ex. 1001). I have been informed that the ’138 patent
`
`claims priority to February 9, 2011.
`
`18.
`
`I have also reviewed the following references, all of which I
`
`understand to be prior art to the ’138 patent:
`
` French Patent Publication No. FR2554302A1, published May 3,
`1985 (“Gärtner,” Ex. 1004).
`
`5
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
` International Publication WO-2004097520, published November
`11, 2004 (“Mourou,” Ex. 1005) .
`
` I.M. Beterov et al., Resonance radiation plasma (photoresonance
`plasma), Sov. Phys. Usp. 31 (6), 535 (1988) (“Beterov,” Ex. 1006).
`
` U.S. Patent No. 4,901,330, filed July 20, 1988 (“Wolfram,” Ex.
`1017).
`
`19.
`
`I am being compensated at my normal consulting rate for my work.
`
`My compensation is not dependent on, and in no way affects, the substance of my
`
`statements in this Declaration.
`
`20.
`
`I have no financial interest in Petitioner. I similarly have no financial
`
`interest in the ’138 patent.
`
`II. LEGAL PRINCIPLES
`21.
`I have been informed that a claim is invalid as anticipated under 35
`
`U.S.C. § 102(b) if “the invention was patented or described in a printed publication
`
`in this or a foreign country or in public use or on sale in this country, more than
`
`one year prior to the date of the application for patent in the United States.” I have
`
`also been informed that a 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.
`
`6
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`I have been informed that a claim is invalid as obvious under 35
`
`22.
`
`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
`been obvious at the time the invention was made to a person having
`ordinary skill in the art to which [the] subject matter pertains.
`
`35 U.S.C. § 103(a). 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
`
`predictable variation is likely not patentable. I have also been informed that
`
`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
`23. A person of skill in the art at the time of the alleged invention of the
`
`’138 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
`
`7
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`master’s degree in physics, electrical engineering, or an equivalent field and 4-5
`
`years of work experience with lasers and plasma.
`
`IV. OVERVIEW OF THE ’138 PATENT
`24. The ’138 patent family is directed to a laser sustained plasma light
`
`source for use in, for example, testing and inspection for semiconductor
`
`manufacturing. As depicted in Fig. 1, shown below, the light source claimed in the
`
`’138 patent includes a pressurized chamber (green) containing gas, an ignition
`
`source (blue) for igniting a plasma, a laser (red) for providing energy to the plasma
`
`(yellow) to produce light. (’138 patent, claim 1 (Ex. 1001).)
`
`
`
`’138 Patent, Fig. 1 (Annotated)
`
`25. According to the ’138 patent, prior products relied upon the electrodes
`
`used for ignition to also sustain the plasma, which resulted in wear and
`
`contamination. (’138 patent, 1:33-49 (Ex. 1001).) Thus, a need allegedly arose for
`
`a way to sustain plasma without relying on an electrical discharge. (Id. 1:50-54.)
`
`8
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`26. With respect to igniting the plasma, the specification of the ’138
`
`patent states that the “ignition source can be or can include electrodes, an
`
`ultraviolet ignition source, a capacitive ignition source, an inductive ignition
`
`source, an RF ignition source, a microwave ignition source, a flash lamp, a pulsed
`
`laser, or a pulsed lamp.” (’138 patent at 2:48-51 (Ex. 1001).) The claims were
`
`limited by amendment to embodiments in which the ignition source comprises
`
`electrodes. (Infra IV.A.) However, the specification does not identify any
`
`purported advantages of electrodes as compared with other ignition sources, nor
`
`does the patent identify anything inventive about using electrodes as an ignition
`
`source as compared with other types of ignition sources.
`
`27. The alleged invention involves using a laser to provide energy to
`
`sustain the plasma for a light source. The ’138 patent is a continuation-in-part that
`
`adds the requirement that the laser be configured to operate at a wavelength within
`
`10 nm of a “strong absorption line.” (’138 patent, 10:47-60 (Ex. 1001).) The ’138
`
`patent does not define the term “strong absorption line.” Rather, it identifies “980
`
`nm, 895 nm, 882, nm, or 823 nm” as examples of strong absorption lines. (’138
`
`patent at 34:23-25 (Ex. 1001).) Table 1 below shows the 823 nm (8232 Å), 882
`
`nm (8819 Å), and 980 nm (9800 Å) absorption lines of xenon, which the ’138
`
`patent identifies as strong absorption lines. The 992 nm line is also a strong
`
`absorption line of xenon because it is listed in Table 1 of the ’138 patent with a
`
`9
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`higher absorption than either the 823 or 980 lines. (’138 patent, Table 1 (Ex.
`
`1001).) As noted in the table, these measurements of absorption lines of xenon
`
`were published by Lothar Klein in 1968. (See Lothar Klein, “Measurements of
`
`Spectral Emission and Absorption of a High Pressure Xenon Arc in the Stationary
`
`and the Flashed Modes,” Applied Optics, Vol, 7, No. 4, 677, at 683 (1968) (Ex.
`
`1022).)
`
`
`
`28. The ’138 patent notes that the strong absorption lines at 980 nm and
`
`882 nm in xenon are based on transitions between the 6s energy level and the 6p
`
`energy level. (’138 patent at 35:28-32.) The other “strong absorption lines” of
`
`xenon identified in Table 1 (823 nm and 992 nm) are also based on transitions
`
`from the 6s energy levels to the 6p energy levels. (See, e.g., Saloman, “Energy
`
`Levels and Observed Spectral Lines of Xenon, XeI through XeLIV,” J. Phys.
`
`10
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`Chem. Ref. Data, Vol. 33, No. 3 (2004) at 789-90 (Ex. 1020).) A person of skill
`
`in the art would understand that a transition from the 6s energy levels to the 6p
`
`energy levels involves moving an electron from one of the lowest two excited
`
`states of the atom to the second lowest group of excited states.
`
`29. As discussed below, sustaining a plasma with a laser to produce light
`
`was not new at the time of the alleged invention of the ’138 patent. Multiple prior
`
`art references, including Gärtner, Beterov, and Wolfram disclosed laser-sustained
`
`plasma light sources with the same elements as the ’138 patent: a chamber, an
`
`ignited plasma, and a laser providing energy to a plasma to produce light.
`
`30. Additionally, there was nothing new about operating the laser at a
`
`wavelength near a strong absorption line. For example, Beterov disclosed tuning a
`
`laser onto or near a wavelength corresponding to a strong absorption line of a gas.
`
`Similarly, Wolfram disclosed tuning a laser at a wavelength within 2 nm of a
`
`strong absorption line of an active medium or lasant material such as ions of
`
`chromium, titanium, or one of the rare earth elements.
`
`A.
`
`Summary of the Prosecution History
`
`31. The ’138 patent issued from U.S. Patent Appl. No. 13/024,027, filed
`
`on February 9, 2011. The ’138 patent application is a continuation in part of the
`
`’786 patent application, which is a continuation in part of the ’455 patent
`
`11
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`application, which is a continuation in part of the ’982 parent patent application,
`
`filed March 31, 2006.
`
`32. On July 10, 2012, the PTO issued an office action in which the claims
`
`were rejected. Claim 1 was rejected under 35 U.S.C. § 112, second paragraph, as
`
`being indefinite because the term “high” (in the phrase “high brightness light”) was
`
`a relative term and not defined. (Office Action, dated July 10, 2012, at 2 (Ex.
`
`1009).) Claims 1-8 were rejected under 35 U.S.C. § 102(b) as being anticipated by
`
`Cheymol U.S. Patent Application No. 2006/039435 (“Cheymol”) and Kusunose
`
`U.S. Patent Application No. 2002/0080834 (“Kusunose”). (Id. at 2-5).
`
`33. On November 8, 2012, the applicant submitted a response. In
`
`response to the 35 U.S.C. § 112 rejection, the applicant argued that “high” was not
`
`indefinite based on examples in the specification. (Response to Non-Final Office
`
`Action, dated Nov. 8, 2012, at 2-3 (Ex. 1010).) In response to the 35 U.S.C. § 102
`
`rejections, applicant tried unsuccessfully to distinguish Cheymol and Kusunose
`
`based on their use of an extreme ultraviolet light source, among other purported
`
`distinctions. (Id. at 3-10.)
`
`34. On December 12, 2012, the PTO issued a final office action in which
`
`the Examiner maintained the 35 U.S.C § 112 rejection, stating that “there is no
`
`explicit definition of how bright is a high brightness light source.” (Office Action
`
`Summary, dated Dec. 12, 2012, at 3 Ex. 1011).) The Examiner also maintained the
`
`12
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`35 U.S.C. § 102 rejections in light of Cheymol and Kusuonose, citing no reason
`
`why an extreme ultraviolet light could not be a high brightness light and noting
`
`that both references disclosed ignition sources. (Id. at 4-7).
`
`35. On April 12, 2013, the applicant filed an amendment in which claim 1
`
`was amended, the other claims were withdrawn, and new claims were added.
`
`(Amendment After Final Office Action, dated April 12, 2013, at 2 (Ex. 1012).)
`
`The applicant removed the high brightness light language. The applicant also
`
`added language requiring a laser at a wavelength within 10 nm of a strong
`
`absorption line for producing a substantially continuous, plasma-generated light,
`
`as well as the chamber being pressurized, and an ignition source comprising
`
`electrodes. Amended claim 1 is shown below:
`
`
`
`The applicant then sought to distinguish the newly amended claims from the prior
`
`art. (Id. at 7-9).
`
`36. On May 6, 2013, the newly amended claims were allowed. The
`
`Notice of Allowance stated that the prior art did not disclose a continuously
`
`13
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`sustained plasma and a wavelength within 10 nm of a strong absorption line.
`
`(Notice of Allowability dated May 6, 2013, at 4-5; Ex. 1013). The Examiner
`
`Initiated Interview Summary also noted that the claims were allowed after removal
`
`of the “high brightness” light language, to overcome the 35 U.S.C. § 112 rejection.
`
`(Examiner-Initiated Interview Summary, dated April 29, 2013; Ex. 1025). The
`
`’138 patent issued on September 3, 2013 (’138 Patent; Ex. 1001).
`
`37. The Examiner, however, did not consider Gärtner, which discloses a
`
`pressurized chamber with electrodes and a continuous laser sustaining a plasma.
`
`Nor did the Examiner consider Beterov or Wolfram, which disclosed lasers
`
`supplying energy within 10 nm of strong absorption lines, and which would have
`
`been obvious to combine with Gärtner.
`
`V. CLAIM CONSTRUCTION
`A.
` “Light source”
`38.
`
` “Light source” should be construed to mean “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 (1µm)), middle infrared (1 µm to 10 µm),
`
`or far infrared (10 µm to 1,000 µm) regions of the spectrum.”
`
`14
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`39. 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.1008).) The
`
`Patent Owner publishes a data sheet which is consistent with the ordinary and
`
`customary meaning in that it includes extreme ultraviolet within the meaning of
`
`“light source.” (See, e.g., EQ-10M Data Sheet (describing Energetiq’s EQ-10
`
`“EUV [Extreme Ultraviolet] Light Source” product operating at 13.5 nm, which is
`
`in the ultraviolet range) (Ex. 1007).)
`
`40. Consistent with the ordinary and customary meaning of “light
`
`source,” the ’138 patent states that parameters such as the wavelength of the light
`
`from a light source vary depending upon the application. (’138 patent, 1:30-32
`
`(Ex. 1001).) The specification describes “ultraviolet light” as an example of the
`
`type of light that can be generated: “In some embodiments, the high brightness
`
`1 The term “light” is sometimes used more narrowly to refer only to visible light.
`
`However, references to “ultraviolet light” in the ’138 patent make clear that the
`
`broader meaning is intended. (See, e.g., ʼ138 Patent, 7:40-43; 17:2; 18:25, 32;
`
`21:7; 23:22; 26:27 (Ex. 1001).)
`
`15
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`light 636 includes ultraviolet light.” (’138 patent, 20:20-21 (Ex. 1001); see also id.
`
`at 17:1-4 (discussing the ultraviolet light 136 generated by the plasma 132 of the
`
`light source).)
`
`41. Notably, during prosecution, the Examiner concluded that high
`
`brightness light includes extreme ultraviolet (EUV) light. (Office Action
`
`Summary, dated December 12, 2012, at 2 (“[A]pplicant has failed to distinguish in
`
`either the claims, or in the specification (for the reasons stated above) that EUV is
`
`not a high brightness light source.”) (Ex. 1011).)
`
`42. Therefore, the term “light source” should be construed to mean “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 (1µm)), middle infrared (1 µm
`
`to 10 µm), or far infrared (10 µm to 1,000 µm) regions of the spectrum.”
`
`VI. THE CHALLENGED CLAIMS ARE INVALID
`A. Laser-Sustained Light Sources Were Known Long Before the
`Priority Date of the ’138 Patent
`43. When the application that led to the ’138 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 light from the plasma, and a laser operating
`
`at a wavelength within 10 nm of a strong absorption line. The concept of using a
`
`16
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`laser to sustain a plasma for a light source had been known at least as early as the
`
`1980’s, several decades before the application date.
`
`44. For example, in 1983, Gärtner 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. 1004.) As shown in Fig. 1, reproduced below, Gärtner
`
`disclosed a light source with the same features claimed in the ’138 patent: (1) a
`
`chamber 1 (green); (2) an ignition source – pulsed laser 10 (blue), which generates
`
`a plasma 14 (yellow) (3) a laser to produce light – laser 9 (red), which provides
`
`energy to the plasma 14 and produces light 15. (Gärtner at 4:31-5:9 (Ex. 1004).)
`
`Gärtner, Fig. 1 (Annotated)
`
`
`
`17
`
`

`

`B.
`
`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`Sustaining a plasma with a laser operating within 10 nm of a
`strong absorption line was well known in the art.
`45. There was nothing new about operating a laser within 10 nm of a
`
`strong absorption line. Two well understood mechanisms for sustaining plasmas
`
`with an external optical source such as a laser are: 1) resonant or near-resonant
`
`excitation of the plasma, which involves supplying energy at or near an absorption
`
`line, and 2) excitation of collective motions in plasmas (such as the absorption of
`
`laser light by inverse bremsstrahlung), which does not require the laser energy be
`
`at or near an absorption line. (Beterov at 536 (Ex. 1006) (“[A] photoresonance
`
`plasma whose properties are determined by elementary collision-radiation
`
`processes, is naturally distinguish[able] from a laser plasma, in which the
`
`transformation of the energy of the laser radiation into the energy of plasma
`
`particles results from the excitation of collective motions in the plasma”).) In other
`
`words, Beterov explains that the laser radiation required to ignite or sustain the
`
`plasma can be at or near an atomic transition (the first mechanism) or can operate
`
`through other processes that need not have a wavelength that matches an atomic
`
`transition (the second mechanism).
`
`46. Gärtner operates primarily through the second of these mechanisms.
`
`In particular, Gärtner’s laser 9 is a CO2 laser. (Gärtner at 5:3-5 (Ex. 1004).) CO2
`
`lasers, which generally operate at a wavelength of 10.6 µm, were commonly used
`
`during the 1970s and 1980s to ignite or sustain plasmas because they provided high
`
`18
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`power and were cost-effective at the time. (See, e.g., U.S. Patent No. 4,780,608 to
`
`Cross at 5:44-47 (“Carbon dioxide lasers have been used since the output
`
`therefrom is readily absorbed by plasmas and they are available with very high
`
`power in both pulsed and cw operating modes.”) (Ex. 1021).) The CO2 laser 9 in
`
`Gärtner sustains (and is capable of igniting) the plasma primarily through the
`
`process of inverse bremsstrahlung, which is simply the absorption of light (a laser
`
`photon) by an electron in the plasma. This absorption of laser light by the “free”
`
`electrons in the plasma leads to the “collective oscillations” to which Beterov
`
`refers when describing the second mechanism.
`
`47. The first mechanism occurs in plasmas referred to by Beterov as
`
`“photoresonance” and “quasi-photoresonance” plasmas, where the laser supplies
`
`energy at or near an absorption line. For example, Beterov, which was published
`
`in June 1988 in the journal “Soviet Physics Uspekhi” and titled “Resonance
`
`radiation plasma (photoresonance plasma),” discloses generating a plasma by
`
`tuning a laser wavelength to a strong absorption line of a gas or vapor. Beterov
`
`states, “One of the methods of creating a plasma involves the action of optical
`
`resonance radiation on a gas.” (Beterov at 535 (Ex. 1006).)
`
`48. Figure 10 of Beterov provides an example of a light source in which
`
`the laser is tuned to a strong absorption line. Figure 10 shows: 1) a chamber
`
`(green); (2) an ignited plasma (yellow); (3) and a continuous dye laser (red) tuned
`
`19
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph.D.
`to a strong absorption line of the plasma to sustain a plasma that emits light.
`
`(Beterov at 540, Fig. 10 (Ex. 1006).)
`
`Beterov, Fig. 10 (Ex. 1006)
`
`
`
`49.
`
`In this example, the chamber contains sodium (Na) vapor and the
`
`continuous dye laser is “tuned in resonance with the 3p-4d transition (λ = 568.8 or
`
`568.2) of the Na atom.” (Beterov at 538 (Ex. 1006).) A person of skill in the art
`
`would understand that the absorption line based on the 3p-4d transition is a “strong
`
`absorption line” because all of the alkali atoms (lithium (Li), sodium (Na),
`
`potassium (K), rubidium (Rb), and cesium (Cs)) are what is known in physics as
`
`“one electron” atoms and the strengths of alkali atomic transitions are renown as
`
`among the strongest of all atomic lines. Therefore, the Na 3p-4d atomic transition
`
`would absorb at least as strongly as the ’138 patent’s exemplary strong absorption
`
`lines of xenon which are based on 6s to 6p transitions.
`
`50. This approach of supplying energy to a plasma at a laser wavelength
`
`that coincides with, or is near, a strong absorption line became more feasible with
`
`20
`
`

`

`U.S. Patent 8,525,138
`Declaration of J. Gary Eden, Ph