`IPR2014-00578
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`UNITED STATES PATENT AND TRADEMARK OFFICE
`_____________________
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`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`_____________________
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`The Gillette Company
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`Petitioner
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`v.
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`ZOND, LLC
`Patent Owner
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`U.S. Patent No. 6,896,775
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`_____________________
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`Inter Partes Review Case No. 2014-00578
`_____________________
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`PATENT OWNER’s PRELIMINARY RESPONSE
`UNDER 37 CFR § 42.107(a)
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`Patent No. 6,896,775
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`TABLE OF CONTENTS
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`I.
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`INTRODUCTION ..................................................................................................................3
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`II. TECHNOLOGY BACKGROUND ....................................................................................3
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`A. Overview of Plasma Generation Systems ......................................................................3
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`B. The ‘775 Patent: Dr. Chistyakov Invents an Improved Plasma Source. .....................6
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`III. SUMMARY OF PETITIONER’S PROPOSED GROUNDS ........................................12
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`IV. CLAIM CONSTRUCTION UNDER 37 C.F.R. §§ 42.104(B)(3) ...................................13
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`A. Construction of “Weakly Ionized Plasma” and “Strongly Ionized Plasma” ...........13
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`B. Construction of “Ionizing a Feed Gas” (Claim 15) .....................................................15
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`V. PETITIONER HAS FAILED TO SHOW A REASONABLE LIKELIHOOD
`OF PREVAILING. ..............................................................................................................16
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`A. Defect in Ground 1: Petitioner Failed To Demonstrate That Independent
`Claim 1 is Obvious In View of Mozgrin Combined with Kudryavtsev and
`Mozgrin’s Thesis ........................................................................................................16
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`1. Overview of Independent Claim 1. .......................................................................16
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`2. Legal Standards for Comparison of the Claim to the Prior Art. ...........................17
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`3. Scope and Content of Prior Art. ..............................................................................19
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`a. Mozgrin’s Thesis Is Not Prior Art. .......................................................................19
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`b. Overview of Mozgrin ..........................................................................................21
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`c. Overview of Kudravtsev .....................................................................................22
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`4. Differences Between Claim 1 and the Prior Art. ....................................................26
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`a. Differences Between Mozgrin and Claim 1 .........................................................26
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`b. Petitioner Failed to Prove Inherency ....................................................................28
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`c.
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`Incompatibilities of Kudryavtsev and Mozgrin ....................................................30
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`d. Differences Between Claim 1 and Kudravtsev .....................................................33
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`e. Conclusion ............................................................................................................33
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`B. Defect in Ground 1: Petitioner Failed To Demonstrate That Independent
`Claim 15 is Obvious In View of Mozgrin Combined with Kudryavtsev
`and Mozgrin’s Thesis .................................................................................................33
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`C. Defect in Ground 1: Petitioner Failed To Demonstrate A Reasonable
`Likelihood That the Dependent Claims Are Obvious ............................................36
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`1. Dependent Claims 2, 7, 13, 18, 23, 29. ...................................................................36
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`2. Dependent Claims 4, 5 .............................................................................................37
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`3. Dependent Claim 6 ...................................................................................................38
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`4. Dependent Claims 7, 12, 13, 22, 23 and 29 ............................................................42
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`D. Defect in Grounds 3, 7: Petitioner Failed To Demonstrate A Reasonable
`Likelihood That the Dependent Claim 27 is Obvious In View of Li ....................43
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`E. Defect In Ground 4: Petitioner Failed To Demonstrate That Parent Claims
`1, 15 are Obvious In view of Wang Combined with Kudryavtsev ........................43
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`1. Overview of Wang. .............................................................................................44
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`2. Differences Between Wang and the Claims. ........................................................46
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`3. Petitioner Failed To Prove Wang Inherently Implements the Claimed
`Type of Ionization. ...........................................................................................50
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`4. Conclusion: Petitioner Fails to Show a Reasonable Likelihood of
`Prevailing on Ground 4 Because They Fail to shown that Claims 1,
`15 are Obvious in View of Wang Combined With Kudryavtsev. ..............52
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`F. Defect in Ground 4: Petitioner Failed To Demonstrate That Dependent
`Claims Are Obvious Wang et al ...............................................................................52
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`1. Dependent Claims 4, 5 .........................................................................................53
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`2. Dependent Claim 6 ..............................................................................................55
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`3. Dependent Claims 7, 12, 13, 22, 23 and 29 .......................................................57
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`VI. CONCLUSION ....................................................................................................................57
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`I.
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`Introduction
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`Patent No. 6,896,775
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`The present petition for inter partes review of U.S. Patent No. 6,896,775
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`(“the ‘775 patent”) is first of two petitions filed by the Gillette Company
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`challenging the ‘775 patent. This petition challenges two of the patent’s
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`independent claims (1, 15) and all claims that depend from claims 1, 15.
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`The independent claims 1, 15 are directed to a method and apparatus for
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`etching material from a substrate using a strongly-ionized plasma formed by a
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`particular type of multi-stage ionization process in which neutral atoms in a
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`weakly ionized gas are first excited from the ground state, and in which
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`secondary electrons are formed from a cathode. The secondary electrons
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`interact with the excited atoms to thereby ionize them to form a strongly
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`ionized plasma. This is in contrast to a more conventional ionization process
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`in which atoms are ionized directly from the ground state, without first
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`achieving an excited state.
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`The Petition challenges claims 1 and 15 based on two prior art
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`references, Mozgrin1 and Wang,2 combined with a prior art patent by
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`1 Ex. 1002, Mozgrin.
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`2 Ex. 1008, Wang patent No. 6,413,382 (“Wang”). 2 Ex. 1008, Wang patent No. 6,413,382 (“Wang”).
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`Kudryavtsev.3 Neither Mozgrin nor Wang discuss or even hint of the type of
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`ionization process of the claims. So the Petition cites to Kudryavtsev as
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`alleged proof that Mozgrin and Wang inherently implement the claimed type
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`of multi-stage ionization. But the Petition falls far short of proving such
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`inherency. As we will explain below, Kudryavtsev predicts that a tubular
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`electrode structure may or may not yield multi-stage ionization depending on a
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`variety of conditions, namely, the gas pressure p, the radius R of the tubular
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`electrode structure, the strength of the applied electric field E, and the density
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`of ground state argon atoms, n1. Therefore Kudryavtsev does not prove that
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`Mozgrin’s or Wang’s radically different electrode structures and operating
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`conditions would inherently provide the claimed multi-stage ionization.
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`For example, both Mozgrin and Wang use electrodes that are spaced
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`closely spacer to each other than Kudryavtsev’s electrodes, and which were
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`immersed in a magnetic field that can dramatically influence ion formation
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`and ion density. Yet Kudryavtsev does not consider such a magnetic field in
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`his mathematical model or in his experimental set up. Therefore, there is no
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`indication in Kudryavtsev of how the presence of the magnetic field in
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`Mozgrin and Wang would influence the type of ionization. Accordingly, the
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`3 Ex. 1003, Kudryavtsev.
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`Petition fails to show a reasonable likelihood that independent claims 1, 15 are
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`unpatentable over the cited art, and therefore review of the challenged
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`dependent claims should be categorically denied on this basis alone.
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`For all of the above reasons and the additional reasons stated below, the
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`Petition should be denied because it does not precisely state the relief
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`requested4 and fails to demonstrate a reasonable likelihood that any challenged
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`claim is unpatentable.5
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`II. Technology Background
`A. Overview of Plasma Generation Systems
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`The claims at issue in this petition are all directed to a method and
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`apparatus for etching material from a substrate with ions from a strongly-
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`ionized plasma. “Sputter etching is the ejection of atoms form the surface of a
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`substrate due to energetic ion bombardment.”6
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` A “plasma” is a gaseous mixture of electrons, positive ions and neutral
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`molecules that can be formed by applying a strong electric field to a gas. A
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`simplified illustration of a plasma formed between a pair of electrodes 238, 216
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`4 37 C.F.R. § 42.104(b).
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`5 37 C.F.R. § 42.108(c).
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`6 Ex. 1001, ‘775 Patent, co. 1, lines 14 – 15.
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`is shown below in figure 2B of the related U.S. patent number 7,604,716 patent
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`(the ‘716 Patent):7
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`A plasma is on average electrically neutral because there are approximately as
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`many negative electrons in the plasma as positive ions. However, the density
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`of charged particles can vary greatly depending on the strength of the applied
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`electric field and the length of time it is applied.
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`Figure 2D from the ‘716 patent below shows a “strongly ionized plasma”
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`having a significantly higher density of charged particles than in the figure
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`above, due in part to a stronger electric field applied across the electrodes:
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`7’716 Patent, Fig. 2B.
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`The ‘775 patent explains that if the plasma has a high concentration of
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`ions in certain regions, then there is a corresponding lack of uniformity in the
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`etching of the substrate by ion bombardment.8 One way to increase
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`uniformity is to apply more power to the plasma to increase ion density.
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`However, “the amount of applied power that is necessary to achieve a
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`significant increase in uniformity can increase the probability of generating an
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`electrical breakdown condition leading to an undesirable electrical discharge
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`(an electrical arc) in the chamber 104.”9 Accordingly, Dr. Chistyakov
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`describes in the ‘775 patent techniques for increasing the ion density in a
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`plasma, and the uniformity of ions over the surface of a substrate to be etched.
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`8 Ex. 1001, ‘775 Patent, col. 3. lines 34 – 44.
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`9 Ex. 1001, ‘775 Patent, col. 3, lines 52 – 56.
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`B. The ‘775 Patent: Dr. Chistyakov Invents an Improved
`Plasma Source.
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`Dr. Chistyakov invented an improved plasma device for etching material
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`from a substrate. The device combines a pair of electrodes and magnet for
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`generating a electric and magnetic fields in the region proximate to the
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`cathode, to thereby induce a special type of ionization for etching material
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`from a substrate located near the cathode. A cross-sectional side view of one
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`embodiment is shown in figure 2 of the patent reproduced below:
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` In this figure, the cathode is separated from the anode 238 by a gap 244,
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`and the substrate to be etched is located directly beneath the cathode as
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`shown.10 A bias voltage source 214 applies a voltage to the substrate so that
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`the substrate is at a negative potential relative to the cathode, thereby causing
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`positive ions formed by the electrode to accelerate into the substrate thereby
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`etching the surface of the substrate.11
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`To create such ions, a neutral gas flows in the gap 244 between a
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`cathode 216 and anode 238 where is it ionized by an electric field across the
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`gap.12 The patent explains that “the dimensions of the gap 244 and the total
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`volume in the region 245 are parameters in the ionization process as described
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`herein.”13
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` A voltage is applied across the electrodes, wherein the voltage is chosen
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`to ionize the gas to form a weakly ionized plasma whose conductivity is
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`chosen to “greatly reduce or prevent the possibility of a breakdown condition
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`when high power is applied to the plasma.14 A magnetic field 245 is generated
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`10 Ex. 1001, ‘755 patent, col. 5, lines 15 – 18.
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`11 Ex. 1001, ‘755 patent, col. 7, lines 59 - 65.
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`12 Ex. 1001, ‘755 patent, col. 5, lines 15 – 18.
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`13 Ex. 1001, ‘755 patent, col. 5, lines 21 - 24.
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`14 Ex. 1001, ‘755 patent, col. 6, lines 6 – 9; col. 7, lines 13 – 15.
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`proximate to the cathode 216 to trap electrons in the weakly-ionized plasma at
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`a location proximate to the cathode surface as shown.15
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`The system then applies a strong electrical pulse across the plasma that
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`generates an electric field that produces the optimum conditions for exciting
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`neutral atoms in the weak plasma, and to cause ions in the plasma to strike the
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`cathode to thereby knock “secondary electrons” from the cathode.16 These
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`secondary electrons are also trapped by the magnetic field in the region near
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`the cathode surface.17
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`These secondary electrons from the cathode surface then interact with
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`the excited atoms in the plasma, causing them to ionize and thereby increase
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`the ion density in the plasma. The weakly ionized plasma, the magnetic field,
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`the dimensions of the gap and the corresponding electric pulse thus cooperate
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`to achieve a strongly ionized plasma for etching using a multi-stage ionization
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`process.
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`Dr. Chistyakov further teaches that the type of electric pulse applied to
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`the weakly ionized plasma in combination with the dimensions of the gap
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`15 Ex. 1001, ‘755 patent, col. 5, lines 31 – 58; col. 9, lines 31 – 33..
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`16 Ex. 1001, ‘775 Patent, col. 9, lines 14 - 17.
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`17 Ex. 1001, ‘775 Patent, col. 9, lines 31 - 32.
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`between the electrodes can together determine whether the gas atoms directly
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`ionize from the ground state, or first enter an excited state and then ionize
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`from the exited state.18 The specification of the ‘755 patent explains the two
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`types of ionization in more detail and the role of these parameters in more
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`detail.
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`The typical ionization process is referred to as “direct ionization” or
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`“atomic ionization by electron impact.”19 In this ionization process, a free
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`electron collides with a neutral atom with enough energy to ionize the atom,
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`thereby producing another free electron.20
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`In the multi-stage ionization process described in the ‘775 patent, the
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`strong electric field applied to a weakly ionized plasma is chosen to excite
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`atoms in the weakly ionized plasma from the ground state into an excited
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`state. The patent teaches that this type of ionization (in which ions are first
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`excited before being ionized), can be promoted by tailoring the parameters of
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`the electric pulse for the system’s electrode gap and other operating conditions
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`of the plasma.
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`18 Ex. 1001, ‘775 Patent, col. 8, line 52 – col. 9, line 22.
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`19 Ex. 1001, ‘775 Patent, col. 3, lines 15 - 27.
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`20 Ex. 1001, ‘775 Patent, col. 3, lines 15 - 27.
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`First, the patent explains the electrodynamics behind atom excitation
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`and ion formation. It says that a ground state atom requires more energy to
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`directly ionize that to enter an excited state:
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`For example, an argon atom requires an energy of about 11.55 eV
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`to become excited …. while neutral atoms require about 15.76 eV
`of energy to ionize.21
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`Once an atom is in an excited state, it obviously requires less energy to ionized
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`than is required to directly ionize the atom from the ground state:
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`The excited [argon] atoms only require about 4 eV of energy to
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`ionize while neutral atoms require about 15.76 eV of energy to
`ionize.22
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`The patent also explains the formation of secondary electrons from the
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`cathode, and how they are trapped by the magnetic field in the same region
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`where the excited atoms reside.23 Since relatively little energy is required to
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`ionize such excited atoms, the secondary electrons interact with the excited
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`atoms to further increase the density of the plasma in that region.24
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`21 Ex. 1001, ‘775 Patent, col. 9, lines 17 – 19, 26 - 27.
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`22 Ex. 1001, ‘775 Patent, col. 9, lines 25 - 28.
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`23 Ex. 1001, ‘775 Patent, col. 9, lines 23 – 35.
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`24 Ex. 1001, ‘775 Patent, col. 9, lines 27 - 35.
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`Next, the patent explains how the electric field in the gap influences the
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`type of ionization that occurs. The ‘775 patent says that a multi-stage
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`ionization (in which ions are first excited before being ionized), can be
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`promoted by tailoring the parameters of the electric pulse for the system’s
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`electrode gap and other operating conditions of the plasma.
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`The dimensions of the gap 244 and the parameters of the applied
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`electric field 260 are chosen to determine the optimum condition
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`for a maximum rate of excitation of the atoms in the region 245.
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`For example, an argon atom requires an energy of about 11.55 eV
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`to become excited. Thus, as the feed gas 264 flows through the
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`region 245, the weakly-ionized plasma is formed and the atoms in
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`the weakly-ionized plasma undergo a stepwise ionization process.
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`***
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`Under appropriate excitation conditions, the portion of the energy
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`applied to the weakly-ionized plasma that is transformed to the
`excited atoms is very high for a pulsed discharge in the feed gas.25
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` The ‘775 patent also explains the relationship between the size of the electrode
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`gap and the applied voltage pulse, stating that they are together chosen to
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`optimize the excitation of atoms:
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`[T]he distance or gap 244 between the cathode 216 and the anode
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`238 is chosen so as to maximize the rate of excitation of the atoms.
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`25 Ex. 1001, ‘775 Patent, col. 9, lines 14 – 22; lines 56 - 61.
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`The value of the electric field 260 in the region 245 depends on the
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`voltage level applied by the pulsed power supply 234 (FIG. 2) and
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`the dimensions of the gap 244 between the anode 238 and the
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`cathode 216.
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`***
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`The parameters of the applied electric field 260 are chosen to
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`determine the optimum condition for a maximum rate of
`excitation of the atoms in the region 245.26
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`The claims at issue in this petition all directed to a method and apparatus
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`for generating a strongly-ionized plasma using the type of multi-stage
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`ionization described above for use in etching a substrate. The Petition alleges
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`that these claim are obvious in view of the prior art references shown in the
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`following summary of the Petitioner’s proposed grounds.
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`III. Summary of Petitioner’s Proposed Grounds
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`Ground
`1
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`2
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`3
`4
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`Claims
`1-7, 9 – 26,
`28, 29
`8
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`27
`1-7, 9 – 26,
`28, 29
`8
`17
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`Art
`Mozgrin, Kudryavtsev, Mozgrin Thesis
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`Mozgrin, Kudryavtsev, Mozgrin Thesis,
`Kouznetsov
`Mozgrin, Kudryavtsev, Mozgrin Thesis, Li
`Wang, Kudryavtsev, Mozgrin Thesis
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`5
`6
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`Wang, Kudryavtsev, Mozgrin Thesis, Kouznetsov
`Wang, Mozgrin, Kudryavtsev, Mozgrin Thesis,
`Kouznetsov
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`26 Ex. 1001, ‘775 Patent, col. 8, line 64 – col. 9, line 2; col/ 9, lines 14 - 17.
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`27
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`Wang, Kudryavtsev, Mozgrin Thesis,
`Kouznetsov, Li
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`IV. Claim Construction Under 37 C.F.R. §§ 42.104(b)(3)
`Pursuant to Rule §42.104(b)(3), the Petitioner “must identify [] how the
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`claim is to be construed” for purposes of comparing the challenged claim to the
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`cited art. The present Petition construes only the claimed phrases “strongly-
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`ionized plasma” and “weakly-ionized plasma.” For all other claim language it
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`offers no explicit construction or parsing of the claim, inviting the reader to
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`infer the Petitioner’s interpretation of the claim language from its allegations
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`that the claimed features are taught by the prior art.
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`A. Construction of “Weakly Ionized Plasma” and “Strongly
`Ionized Plasma”
`The Petitioner’s proposed constructions of the claim terms “strongly
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`ionized plasma,” and “weakly ionized plasma” are wrong because they are not
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`the broadest reasonable constructions consistent with the specification. In
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`particular, the Petitioner’s proposed construction of “strongly ionized plasma”
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`as a “higher density plasma” is wrong because the proposed construction reads
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`the claim term “ionized” out of the claim. That is, the Petitioner’s proposed
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`construction of “strongly ionized plasma” is incomplete because it does not
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`specify what the term “density” refers to.
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`The proper construction of “strongly ionized plasma” is “a plasma with
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`a relatively high peak density of ions.” This proposed construction specifies
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`that the term “density” refers to ions and therefore, is consistent with the claim
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`language. Moreover, the proposed construction is also consistent with the
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`specification of the ‘716 patent which indicates that a strongly ionized plasma
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`is also referred to as a “highly-ionized plasma.”27 The term ‘strongly-ionized
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`plasma’ is defined herein to mean a plasma with a relatively high peak density of
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`ions.
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`For similar reasons, the proper construction of the claim term “weakly
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`ionized plasma” is “a plasma with a relatively low peak density of ions.” In
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`particular, the specification of the ‘716 patent says that “a weakly ionized
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`plasma [has] a relatively low-level of ionization”28 Furthermore, the
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`specification of a related patent number 6,806,652 (“the ‘652 Patent”) states
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`that “[t]he term ‘weakly-ionized plasma’ is defined herein to mean a plasma
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`with a relatively low peak plasma density. The peak plasma density of the
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`weakly ionized plasma depends on the properties of the specific plasma
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`processing system.”
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`27 ‘716 patent, col. 7, lines 15 - 16.
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`28 ‘716 patent, col. 6, lines 22 - 24.
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`B. Construction of “Ionizing a Feed Gas” (Claim 15)
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`The Petitioner does not construe the claimed phrase “ionizing a feed
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`gas,” but its comparison to the claim treats as superfluous the word “feed” in
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`the expression “feed gas” – “a methodology of claim construction that [the
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`Federal Circuit] has denounced.”29 Even under the broadest reasonable
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`interpretation standard, the claim term “feed” cannot be read out of the claim
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`and cannot be deemed superfluous over the word it qualifies, “gas.”
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`“A feed gas,” as its name implies, is a flow of gas. As explained in the
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`specification, the “electric field in the gap 530 between the electrode 452 and
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`the cathode 216 is adapted to ignite the plasma from the feed gas flowing
`through the gap 530.”30 The claimed step thus requires ionization of gas in the
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`chamber that is being fed into the chamber. Accordingly the claimed step of
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`“ionizing a feed gas” refers to ionization of a gas as that gas is being fed to the region
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`where ionization occurs:
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`Claim Language at Issue
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`“ionizing a feed gas”
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`Proposed Construction
`ionization of a gas while that gas is
`being fed to the region where
`ionization occurs
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`29 Stumbo v. Eastman Outdoors, Inc., 508 F.3d 1358, 1362 (Fed. Cir. 2007).
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`30 Ex. 1001, ‘775 Patent, col. 18, lines 14 - 18.
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`V.
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`Petitioner Has Failed to Show a Reasonable Likelihood of Prevailing.
`A. Defect in Ground 1: Petitioner Failed To Demonstrate That
`Independent Claim 1 is Obvious In View of Mozgrin
`Combined with Kudryavtsev and Mozgrin’s Thesis
`1. Overview of Independent Claim 1.
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`The challenged claim 1 is generally directed to an apparatus that
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`combines several elements that cooperate to cause a type of multi-stage
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`ionization process that forms a strongly ionized plasma for use in etching
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`material from a substrate.
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`An ionization source generates a weakly ionized plasma proximate to
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`the cathode. A magnet is positioned to generate a magnetic field proximate to
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`the plasma that traps substantial electrons in the weak plasma
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` A power supply produces an electric field across the gap between the
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`cathode and anode that excites atoms in the weakly ionized plasma. The
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`electric field also generates secondary electrons from the cathode that interact
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`with the excited atoms to ionize them, thereby creating a strongly-ionized
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`plasma. This type of multi-stage ionization is different from the typical
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`ionization process in which atoms are directly ionized from their ground state.
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`In the typical ionization process, ground state atoms collide with electrons that
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`have sufficient energy to remove an electron from a gas atom, thereby “directly
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`ionizing” the atoms in a single step. The patent teaches that the claimed type
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`multi-stage ionization is induced by properly choosing the parameters of the
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`electric pulse for a given electrode gap and other operating conditions of the
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`plasma.31
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`In sum, the claim is directed to an apparatus that implements a type
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`multi-stage ionization for forming a strongly ionized plasma for etching
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`material from a substrate. The Petition alleges in Ground 1 that the claim is
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`obvious in view of the combined teachings of Mozgrin, Kudryavtsev and
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`Mozgrin’s Thesis.
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`2.
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`Legal Standards for Comparison of the Claim to the
`Prior Art.
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`The Supreme Court in Graham v. Deere, set forth the legal framework for
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`an obviousness analysis.32 That framework requires consideration of the
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`following factors: (1) the scope and content of the prior art, (2) any differences
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`between the claimed subject matter and the prior art, and (3) the level of skill
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`in the art.
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`31 Ex. 1001, ‘755 Patent, col. 9, lines 14 - 50.
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`32 Graham v. John Deere Co., 383 U.S. 1, 17-18, 148 USPQ 459, 467 (1966); see
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`also KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 399 (2007) (“While the sequence
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`of these questions might be reordered in any particular case, the [Graham]
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`factors define the controlling inquiry.”)
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`Furthermore, “Petitioner[s] must show some reason why a person of
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`ordinary skill in the art would have thought to combine particular available
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`elements of knowledge, as evidenced by the prior art, to reach the claimed
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`invention.”33 Inventions are often deemed nonobvious (and thus patentable)
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`even when all of the claim elements are individually found in the prior art
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`because an “invention may be a combination of old elements.”34 The
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`motivation to combine inquiry focuses heavily on “scope and content of the
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`prior art” and the “level of ordinary skill in the pertinent art” aspects of the
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`Graham factors.35 The Petition did not address either factor.
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`33 Heart Failure Technologies, LLC v. Cardiokinetix, Inc., IPR2013-00183, Paper 12
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`at 9 (P.T.A.B. July 31, 2013) (citing KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398,
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`418 (2007)) (emphasis in original).
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`34 Cross Med. Prods., Inc. v. Medtronic Sofamor Danek, Inc., 424 F.3d 1293, 1321
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`(Fed. Cir. 2005).
`35 Alza Corp. v. Mylan Labs., Inc., 464 F.3d 1286, 1290 (Fed. Cir. 2006) (“We
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`further explained that the ‘motivation to combine’ requirement ‘[e]ntails
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`consideration of both the ‘scope and content of the prior art’ and ‘level of
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`ordinary skill in the pertinent art’ aspects of the Graham test.’”).
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`3.
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`Scope and Content of Prior Art.
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`The scope and content of Mozgrin and Kudryavtsev and the differences
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`between them and the claims36 are summarized below. But the last reference
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`cited in Ground 1, Mozgrin’s Thesis, is not even prior art.
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`a. Mozgrin’s Thesis Is Not Prior Art.
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`Mozgrin’s thesis does not qualify as a prior art printed publication
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`because the Petitioner, who bears the burden of proof, has not shown that the
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`thesis was “sufficiently accessible to the public interested in the art” before the
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`critical date.37 As the Federal Circuit has explained in several cases, a thesis
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`must be “made available” so that an interested person “can locate it,” such as
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`for example via a searchable catalog available before the patent’s effective
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`date.38 In Cronyn, for example, the Federal Circuit held that three theses
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`authored before the relevant date did not qualify as prior art. The court ruled
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`that even though copies of the theses were lodged at several libraries, they had
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`36 See MPEP § 2141.01, 2141.02.
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`37 In re Lister, 583 F.3d 1307 (Fed. Cir. 2009).
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`38 see e.g., In Re Cronyn, 890 F.2d 1158 (Fed. Cir. 1989); and In re Lister, 583 at
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`1311.
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`not been cataloged or indexed by the critical date in a way that would permit
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`the public to locate them:
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`[T]he three student theses were not accessible to the public because
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`they had not been either cataloged or indexed in a meaningful
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`way. … Considering all the facts of this case, we hold that the
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`three student these were not “printed publications’ under 35
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`U.S.C. §102(b).
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`The cover page of Mozgrin’s Thesis bears the notation: “Moscow –
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`1994,” but says nothing of whether or when the public had unrestricted access
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`to the university’s copy, and whether or when the university had a system such
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`as a catalog by which interested persons could locate the thesis. The catalog
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`title reads: “Catalog of Dissertations in Russian (since 1996),” but does not
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`indicate when the Mozgrin Thesis was added to that catalog. The catalog
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`entry bears a copyright notice for the “Ex Libris Group” that provides “library
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`automation solutions.” This merely indicates that Ex Libris software existed
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`sometime in 2002, but fails to say when the software was used to catalog the
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`Mozgrin Thesis. As a matter of law, such evidence fails to establish that the
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`Mozgrin Thesis is prior art. The thesis may have existed in 1994, the earliest
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`date on the document. But that alone would not qualify the thesis as prior
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`art.39
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`b. Overview of Mozgrin
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`Mozgrin reports the results of a variety of experiments he made using
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`two different electrode structures that generated a plasma in the presence of a
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`magnetic field. Mozgrin’s planar electrode structure is shown in the figure to
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`the left, and his bell shaped electrode structure is shown to the right:40
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`Planar Electrodes
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`Shaped Electrodes
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`Mozgrin “filled” the space between the electrodes with either neutral or pre-
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`ionized gas.41 He then applied a square voltage pulse to the gap to form a
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`“high current quasi-stationary plasma.”42
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