UNITED STATES PATENT AND TRADEMARK OFFICE
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`_____________________
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`BEFORE THE PATENT TRIAL AND APPEAL BOARD
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`_____________________
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`
`THE PETITIONERS COMPANY
`Petitioner
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`v.
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`ZOND, LLC
`Patent Owner
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`U.S. Patent No. 7,811,421
`
`_____________________
`
`Inter Partes Review Case No. 2014-00800
`
`Inter Partes Review Case No. 2014-00802
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`Inter Partes Review Case No. 2014-00805
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`____________________
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`DECLARATION OF LARRY D. HARTSOUGH, Ph.D.
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`TABLE OF CONTENTS
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`I.   Education and Professional Background ................................................................................... 1  
`II.   Summary of Opinions: Claims 1 - 48 ...................................................................................... 5  
`III.   Legal Standards ........................................................................................................................ 7  
`A.   Level of Ordinary Skill in the Art ............................................................................ 7  
`B.   Claim Interpretation Issues for Claims 1 - 48 .......................................................... 8  
`C.   Legal Standards for Anticipation ............................................................................. 9  
`D.   Legal Standards for Obviousness ............................................................................. 9  
`IV.   Background Topics ................................................................................................................ 11  
`A.   Voltage, current, impedance and power ................................................................. 12  
`B.   Control systems ...................................................................................................... 14  
`C.   Set point (Controlled Parameter) ............................................................................ 16  
`D.   Power Control vs Voltage Control ......................................................................... 17  
`E.   Magnetron Sputtering History and Operation ........................................................ 20  
`V.   Overview of the ‘421Patent .................................................................................................... 25  
`VI.   Prior Art .................................................................................................................................. 33  
`A.   Wang ...................................................................................................................... 33  
`a.   Wang’s Power Source ..................................................................................................... 34  
`b.   Wang’s Power Pulses ...................................................................................................... 35  
`c.   Arcing in Wang ............................................................................................................... 38  
`d.   Variances between Wang’s Target Power Levels and Actual Power ............................. 42  
`VII.  Conclusion and Opinion Regarding Claim 1 and its Dependent Claims ............................... 45  
`VIII.   Conclusion and Opinion Regarding the Other Claims ..................................................... 48  
`IX.   Additional Conclusions and Opinions Regarding the Dependent Claims ............................. 49  
`A.   Claims 6, 31, 45 ..................................................................................................... 49  
`B.   Claim 44 ................................................................................................................. 53  
`C.   Claims 7, 32 ............................................................................................................ 55  
`D.   Claims 11, 23 ......................................................................................................... 55  
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`E.   Claims 12, 24 .......................................................................................................... 56  
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`I, Larry D. Hartsough, Ph.D., hereby declare:
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`1.
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`I am making this declaration at the request of patent owner
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`Zond, LLC, in the matter of the Inter Partes Reviews (IPRs) of U.S. Patent
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`No. 7,811,421 (the “‘421 Patent”), as set forth in the above caption.
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`2.
`
`I am being compensated for my work in this matter at the rate of
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`$300 per hour. My compensation in no way depends on the outcome of this
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`proceeding.
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`3.
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`The list of materials I considered in forming the opinions set
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`forth in this declaration includes the ‘421 patent, the file history of the ‘421
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`patent, the Petitions for Inter Partes Review, the PTAB’s Institution
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`Decisions, and the prior art references discussed below.
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`I. Education and Professional Background
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`4. My formal education is as follows. I received a Bachelors of
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`Science degree in 1965, Master of Science degree in 1967, and Ph.D. in
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`1971, all in Materials Science/Engineering from the University of California,
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`Berkeley.
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`5.
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`I have worked in the semiconductor industry for approximately
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`30 years. My experience includes thin film deposition, vacuum system
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`design, and plasma processing of materials. I made significant contributions
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`to the development of magnetron sputtering hardware and processes for the
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`metallization of silicon integrated circuits. Since the late 1980’s, I have also
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`been instrumental in the development of standards for semiconductor
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`fabrication equipment published by the SEMI trade organization.
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`6.
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`From 1971-1974, I was a research metallurgist in the thin film
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`development lab of Optical Coating Laboratory, Inc. In 1975 and 1976, I
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`developed and demonstrated thin film applications and hardware for an in-
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`line system at Airco Temescal. During my tenure (1977-1981) at Perkin
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`Elmer, Plasma Products Division, I served in a number of capacities from
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`Senior Staff Scientist, to Manager of the Advanced Development activity, to
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`Manager of the Applications Laboratory. In 1981, I co-founded a
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`semiconductor equipment company, Gryphon Products, and was VP of
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`Engineering during development of the product. From 1984-1988, I was the
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`Advanced Development Manager for Gryphon, developing new hardware
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`and process capabilities. During 1988-1990, I was Project Manager at
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`General Signal Thinfilm on a project to develop and prototype an advanced
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`cluster tool for making thin films. From 1991-2002, I was Manager of PVD
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`(physical vapor deposition) Source Engineering for Varian Associates, Thin
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`Film Systems, and then for Novellus Systems, after they purchased TFS.
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`Since then, I have been consulting full time doing business as UA
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`Associates, where my consulting work includes product development
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`projects, film failure analysis, project management, technical presentations
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`and litigation support.
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`7.
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`Throughout my career, I have developed and/or demonstrated
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`processes and equipment for making thin films, including Al, Ti-W, Ta, and
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`Cu metallization of silicon wafers, RF sputtering and etching, and both RF
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`and dc magnetron reactive sputtering, for example SiO2, Al2O3, ITO
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`(Indium-Tin Oxide), TiN, and TaN. I have been in charge of the
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`development of two sputter deposition systems from conception to prototype
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`and release to manufacturing. I have also specialized in the development and
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`improvement of magnetically enhanced sputter cathodes. I have experience
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`with related technology areas, such as wafer heating, power supply
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`evaluation, wafer cooling,
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`ion beam sources, wafer handling by
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`electrostatics, process pressure control, in-situ wafer/process monitoring,
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`cryogenic pumping, getter pumping, sputter target development, and
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`physical, electrical and optical properties of thin films.
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`8.
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`I am a member of a number of professional organizations
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`including the American Vacuum Society, Sigma Xi (the Scientific Research
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`Society), and as a referee for the Journal of Vacuum Science & Technology.
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`I have been a leader in the development of SEMI Standards for cluster tools
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`and 300mm equipment, including holding various co-chair positions on
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`various standards task forces. I have previously served as a member of the
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`US Department of Commerce’s Semiconductor Technical Advisory
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`Committee.
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`9.
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`I have co-authored many papers, reports, and presentations
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`relating to semiconductor processing, equipment, and materials, including
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`the following:
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`a. P. S. McLeod and L. D. Hartsough, "High-Rate Sputtering of
`Aluminum for Metalization of Integrated Circuits", J. Vac. Sci.
`Technol., 14 263 (1977).
`b. D. R. Denison and L. D. Hartsough, "Copper Distribution in
`Sputtered Al/Cu Films", J. Vac. Sci. Technol., 17 1326 (1980).
`c. D. R. Denison and L. D. Hartsough, "Step Coverage in Multiple
`Pass Sputter Deposition" J. Vac. Sci. Technol., A3 686 (1985).
`d. G. C. D’Couto, G. Tkach, K. A. Ashtiani, L. Hartsough, E. Kim,
`R. Mulpuri, D. B. Lee, K. Levy, and M. Fissel; S. Choi, S.-M.
`Choi, H.-D. Lee, and H. –K. Kang, “In situ physical vapor
`deposition of ionized Ti and TiN thin films using hollow cathode
`magnetron plasma source” J. Vac. Sci. Technol. B 19(1) 244
`(2001).
`
`10. My areas of expertise include sputter deposition hardware and
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`processes, thin film deposition system design and thin film properties. I am a
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`named inventor on twelve United States patents covering apparatus, methods
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`or processes in the fields of thin film deposition and etching. A copy of my
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`CV is attached as Exhibit A.
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`II. Summary of Opinions: Claims 1 - 48
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`11.
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`In my opinion, the plasma generation methods described in
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`claims 1 through 48 of the ‘421 patent are neither taught by the cited art nor
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`obvious in view of them.
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`12. Every challenge in Petitions IPR2014-00800, IPR2014-00802,
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`and IPR2014-00805 is premised on the argument that Wang anticipates the
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`independent claims of the ‘421 patent. As I explain below, Wang does not
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`anticipate these claims for at least the reason that the continuous DC power
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`that the Petitions rely upon in their anticipation analysis does not teach the
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`claimed generation of a voltage pulse for creating a weakly ionized plasma
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`without arcing. The continuous DC power source is not a voltage pulse as
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`claimed for at least the reason that it is a continuous DC background and
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`because it causes an arc upon creation of the plasma.
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`13. Furthermore, the independent claims also require that certain
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`characteristics of the voltage pulse be “chosen” to increase a density of ions
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`in a strongly ionized plasma, while still complying with the claimed
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`requirements of creating a weakly ionized plasma and “without an
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`occurrence of arcing.” Wang does not teach these claim elements for at least
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`the reason that its power supply chooses a target power level and thus allows
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`the voltage characteristics to vary to any level needed to achieve the chosen
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`target power. For at least these reasons, Wang does not anticipate any of the
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`independent claims.
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`14.
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` This same issue arises again with dependent claims 11, 12, 23
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`and 24. Claims 11, 23 require that the power supply in the sputtering
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`sources of parent claims 1, 17 generate a constant voltage. Since Wang’s
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`power supply is designed to emit pulses having a target power level, its
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`voltage will vary as needed to obtain the target power. Therefore it does not
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`“generate a constant voltage.”
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`15.
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` Claims 12, 24 requires that the chosen rise time of the voltage
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`pulse generated by the sputtering sources of patent claims 1, 17 is also
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`chosen to increase the rate at which ions are formed in the strongly ionized
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`plasma, again without an occurrence of arcing. I do not agree that the
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`Wang’s power supply for generating a power pulse having a target power
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`level teaches the generation of a voltage pulse having a rise time that is
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`“chosen to increase an ionization rate of the strongly ionized plasma” as
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`recited in claims 12, 24: Wang’s system does not choose a voltage rise time
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`– it allows voltage to rise at whatever rate is needed to achieve a desired
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`power level.
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`16. Claims 6, 31, and 45 require a flow of feed gas that diffuses or
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`spreads a strongly ionized plasma, as for example depicted in figures 5c and
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`5D. It is my opinion that the combination of Wang and Lantsman does not
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`teach the claimed control of feed gas to diffuse a strongly ionized plasma as
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`recited in claims 6, 7, 31, 32, and 45. Neither Wang nor Lantsman make any
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`mention of any control of a feed gas to cause a plasma to spread as required
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`by the claims, nor does their disclosure suggest it to one skilled in the art.
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`They therefore certainly do not teach such diffusion of a strongly ionized gas
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`so as to allow a strongly ionized plasma to absorb more power as required
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`by claims 7, 32. For essentially the same reasons, this art does not teach or
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`suggest the diffusion of a weakly ionized plasma as recited in claim 44.
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`III. Legal Standards
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`17.
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`In this section I describe my understanding of certain legal
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`standards. I have been informed of these legal standards by Zond’s
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`attorneys. I am not an attorney and I am relying only on instructions from
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`Zond’s attorneys for these legal standards.
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`A. Level of Ordinary Skill in the Art
`18.
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`I understand that a person of ordinary skill in the art provides a
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`reference point from which the prior art and claimed invention should be
`
`viewed. This reference point prevents one from using his or her own insight
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`or hindsight in deciding whether a claim is obvious.
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`19.
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`In my opinion, given the disclosure of the ‘421 patent and the
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`disclosure of the prior art references considered here, I consider a person of
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`ordinary skill in the art at the time of filing of the ‘421 patent to be someone
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`who holds at least a bachelor of science degree in physics, material science,
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`or electrical/computer engineering with at least two years of work
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`experience or equivalent in the field of development of` plasma-based
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`processing equipment. I met or exceeded the requirements for one of
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`ordinary skill in the art at the time of the invention and continue to meet
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`and/or exceed those requirements.
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`B. Claim Interpretation Issues for Claims 1 - 48
`20.
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`I understand that the Board tentatively construed “strongly-
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`ionized plasma” as “a plasma with a relatively high peak density of ions,”
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`and has construed “weakly-ionized plasma” as “a plasma with a relatively
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`low peak density of ions,”1 For purposes of this analysis, I have used this
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`interpretation.
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`21.
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`I understand
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`that Zond has proposed
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`the
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`following
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`interpretation of the claimed requirement that a voltage pulse “creates a
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`weakly ionized plasma ….”:
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`1 IPR2014-00800, Decision at p. 10; IPR 2014-00802, Decision at p. 11; IPR
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`2014-00805, Decision at p. 9 – 10.
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`Claim Language
`a voltage pulse … that creates a
`weakly-ionized plasma and then a
`strongly-ionized plasma from the
`weakly-ionized plasma without an
`occurrence of arcing
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`
`
`Construction
`A voltage pulse that ignites a gas from a state
`in which there is no plasma to a state in which
`a plasma exists, wherein the plasma is initially
`a weakly-ionized plasma and then a strongly-
`ionized plasma that is formed from the
`weakly-ionized plasma without an occurrence
`of arcing
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`
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`For purposes of this declaration, I have used the proposed interpretation,
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`which is consistent with my understanding of the language and the
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`specification.
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`C. Legal Standards for Anticipation
`22.
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`I understand that a claim is anticipated under 35 U.S.C. § 102 if
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`(i) each and every element and limitation of the claim at issue is found either
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`expressly or inherently in a single prior art reference, and (ii) the elements
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`and limitations are arranged in the prior art reference in the same way as
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`recited in the claims at issue.
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`D. Legal Standards for Obviousness
`23.
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`I understand that obviousness must be analyzed from the
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`perspective of a person of ordinary skill in the relevant art at the time the
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`invention was made. In analyzing obviousness, I understand that it is
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`important to understand the scope of the claims, the level of skill in the
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`relevant art, the scope and content of the prior art, the differences between
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`the prior art and the claims, and any secondary evidence of non-obviousness.
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`I have not been asked to study or analyze any secondary considerations of
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`non-obviousness.
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`24.
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`I understand that even if a patent is not anticipated, it is still
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`invalid if the differences between the claimed subject matter and the prior art
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`are such that the subject matter as a whole would have been obvious at the
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`time the invention was made to a person of ordinary skill in the pertinent art.
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`25.
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`I also understand that a party seeking to invalidate a patent as
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`obvious must demonstrate that a person of ordinary skill in the art would
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`have been motivated to combine the teachings of the prior art references to
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`achieve the claimed invention, and that the person of ordinary skill in the art
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`would have had a reasonable expectation of success in doing so. This is
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`determined at the time the invention was made. I understand that this
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`temporal requirement prevents the forbidden use of hindsight. I also
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`understand that rejections for obviousness cannot be sustained by mere
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`conclusory statements and that the Petitioners must show some reason why a
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`person of ordinary skill in the art would have thought to combine particular
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`available elements of knowledge, as evidenced by the prior art, to reach the
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`claimed invention.” I also understand that the motivation to combine
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`inquiry focuses heavily on “scope and content of the prior art” and the “level
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`of ordinary skill in the pertinent art.”
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`26.
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`I have been informed and understand that the obviousness
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`analysis requires a comparison of the properly construed claim language to
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`the prior art on a limitation-by-limitation basis.
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`IV. Background Topics
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`27. The ‘421 patent describes a system for using a voltage pulse to
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`create a weakly-ionized plasma and then to form a strongly ionized plasma
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`from the weakly-ionized plasma without arcing. The pulse’s amplitude,
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`duration and rise time are chosen to achieve these results and to increase a
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`density of ions in the strongly-ionized plasma.
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`28. To provide context for understanding the issues identified in the
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`Board’s Decision and addressed in this report, I briefly review well-known,
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`basic relationships between voltage, current, impedance and power. I also
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`review some basic concepts of control systems, such as used to control the
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`output of power supplies for magnetron sputtering. I then give a brief
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`overview of magnetron sputtering before discussing the ‘421 patent and the
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`prior art.
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`A. Voltage, current, impedance and power
`29. As is commonly known, when a voltage “V” is applied across
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`an impedance “I,” an electric field is generated that forces a current I to flow
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`through the impedance. For purely resistive impedance, the relation
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`between the voltage and the resultant current is given by: V = I * R
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`30. A common analogy is that voltage is like a pressure that causes
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`charge particles like electrons and ions to flow (i.e., current), and the amount
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`of current depends on the magnitude of the pressure (voltage) and the
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`amount of resistance or impedance that inhibits the flow. The ‘421 patent
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`and the prior art considered here involve the flow of current through an
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`assembly having a pair of electrodes with a plasma in the region between
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`them. The effective impedance of such an assembly varies greatly with the
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`density of charged particles in the region between the electrodes. Although
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`such an impedance is more complex than the simple resistive impedance of
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`the above equation, the general relation is similar: a voltage between the
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`electrode assembly forces a current to flow through the plasma, such that the
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`amount of current is determined by the amplitude of the voltage and the
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`impedance of the plasma. Thus, the current through the electrode assembly
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`increases with the electrode voltage and, for a given electrode voltage, the
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`current will increase with a drop in the impedance of the plasma.
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`31. The impedance varies with the charge density of the plasma:
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`With a high density of charged particles the impedance is relatively small,
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`and with a low density of charged particles the impedance is relatively large.
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`Simply, the more ions and electrons to carry the charge, the less the
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`resistance. However, the charges and fields react with each other in a very
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`complicated manner.
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`32.
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`In response to the electric field in the region between the
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`electrodes (i.e., the voltage across the electrodes), all charged particles in the
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`region (the electrons and positive ions) feel a force that propels them to
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`flow. This flow is an electric current “I.” Obviously, the amount of current
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`depends upon the number of charged particles. When there are no charged
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`particles (i.e., no plasma), there is no current flow in response to the electric
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`field. In this condition, the impendence of the electrode assembly is
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`extremely high, like that of an open circuit. But when there is a dense
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`plasma between the electrodes (with many charged particles), a substantial
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`current will flow in response to the electric field. In this condition, the
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`impendence of the electrode assembly is very low. Thus, in general, the
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`impedance of an electrode assembly varies greatly with the charge density of
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`the plasma: The impedance is effectively infinite (an open circuit) when
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`there is no plasma, and is very low when the charge density is very high.
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`33.
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` It is also well known that electric power (P) is the product of
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`voltage (V) and current (I): P = V * I. Thus, for a given voltage across an
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`electrode assembly, the amount of power will depend on the amount of
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`corresponding current flowing through the electrode assembly. If there is
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`no current flow (such as when there is no plasma between the electrodes),
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`the power is zero, even if the voltage across the electrodes is very large.
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`Similarly, at very low electrode voltages, the power can still be quite high if
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`the current is large.
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`34. But first, to provide context for understanding the ‘421 patent, I
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`consider below some known basic principles of control systems (such as
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`used in all power supplies and all such control systems) for controlling a
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`parameter such as voltage amplitude.
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`B. Control systems
`35. The pulsed power supply 234 mentioned in the ‘421 patent is an
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`example of a control system. This system controls the voltage amplitude of
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`a voltage pulse. A simplified block diagram of a common feedback control
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`system is shown the figure below from a text by Eronini.2
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`2 Ex. 2010, Eronini Umez-Eronini, System Dynamics and Control, Brooks
`Cole Publishing Co., CA, 1999, pp. 10-13.
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`Figure 1 Control system simplified block diagram
`36. The “reference input signal” represents a “desired value” or
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`“set-point” of the controller. The control system directly controls the
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`“controlled variable.” In response to the difference between the set-point
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`and a feedback signal (which represents the condition of the controlled
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`variable), the control system directs the controlled variable in an attempt to
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`reduce the difference to zero, thereby causing the controlled variable to
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`equal the set point value.
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`37. For example, the set-point for filling a water tank may be 1,000
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`gallons, or full. The desired value, set-point or desired level is the value
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`“full” or “1000 gallons.” An open loop control system might just fill the
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`tank for a pre-calibrated time that result in the tank being full. The control
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`system might be set to fill the tank once per day based on historical water
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`usage. However, if water usage is not consistent, the tank may run empty
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`before it is filled, or may overflow because there was less water usage than
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`normal. On the other hand, a closed loop system such as shown above uses
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`feedback control. For example, it measures the water level, and only adds
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`the needed amount. It might have a switch or sensor that detects when the
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`tank is full, and turns off the flow of water. The set-point is the desired
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`value. “Here the comparison of the tank level signal with the desired value
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`of the tank level (entered into the system as a set-point setting) and the
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`turning of the pump on or off are all performed by appropriate hardware in
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`the controller.” 3 Further, a closed loop system could be left on to fill the
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`tank if the level dropped too low. “In feedback control, a measurement of the
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`output of a system is used to modify its input in such a way that the output
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`stays near the desired value4.”
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`C. Set point (Controlled Parameter)
`38. The parameter that is directed to a desired value is called the
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`“controlled variable,” as shown in the figure from Eronini. Eronini’s
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`diagram also shows that while controlling the “controlled variable,” the
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`3 Ex. 2010, Eronini Umez-Eronini, System Dynamics and Control, Brooks
`Cole Publishing Co., CA, 1999, pp. 10-13.
`4 Ex. 2010, Eronini Umez-Eronini, p. 12.
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`system may “manipulate” another control parameter that Eronini calls the
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`“manipulated variable.”
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`39. This terminology is commonly used in other references that
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`describe control systems. A reference by Weyrick, for example, uses the
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`same terminology as Eronini:
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`• “The controlled output is the process quantity being controlled.”
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`• “The manipulated variable is the control signal which the control
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`elements process.”5
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`40. Similarly, Kuo and Sinha also show that the “controlled
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`parameter” is widely understood to mean the parameter being controlled by
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`the control system.6
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`41. With this understanding, I now consider the difference between
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`controlling the amplitude of a voltage and controlling the power.
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`D. Power Control vs Voltage Control
`42. To demonstrate the difference between the control of voltage
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`and the control of power, I will refer to the generic diagram of a feedback
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`control system from Eronini. In a system for controlling voltage, the set
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`point is a specified voltage and the “controlled variable” obviously is
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`5 Ex. 2011, Weyrick at 13
`6 Ex. 2012, Kuo; Ex. 2013, Sinha.
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`voltage. Thus, in a feedback control system as shown in Eronini, a feedback
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`signal representative of the measured voltage is fed back and compared to
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`the desired voltage level or “set point.” Based on the difference between the
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`measured voltage and the desired voltage or set point, the control system
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`drives or restrains the voltage in an attempt to move the actual voltage to
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`match the desired voltage.
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`43.
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`In a system for controlling power, the set point is a specified
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`power value and the controlled variable is power. In such a system, the
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`voltage and/or current can be driven by the control system to whatever levels
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`are needed to achieve the target power level. Thus, in the example of a
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`system for controlling the power of a plasma electrode assembly, if there is
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`no plasma between the electrodes (and therefore little or no current) a
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`controller attempting to achieve a target power level will drive the voltage
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`extremely high in an attempt to achieve the target power P, i.e., P = V * I,
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`(because I is very low or zero in this situation).
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`44.
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` Thus, in a control system for controlling power to a desired set
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`point, voltage will vary as the controller attempts to achieve the desired
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`power level (i.e., a desired product of voltage and current). However, the
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`amplitude of the voltage is not controlled and instead the voltage and/or the
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`current vary as needed to achieve the desired power.
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`45. The rise time of a voltage therefore is a different parameter than
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`the rise time of power. For example, consider a scenario in which a voltage
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`source outputs a constant voltage. If that source is connected across an
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`impedance that gradually drops, the current will increase as the impedance
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`drops. Since power is the product of voltage (here a constant) and current,
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`the power too will rise as the current increases. Thus, in this situation,
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`power rises at rate determined by the rate at which the impedance decreases.
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`But there is no rise in voltage because the source maintains a static, constant
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`voltage at its output in this example. This demonstrates that a rise time in
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`voltage is a different parameter than rise time in power.
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`46. This example can also be used to demonstrate the difference
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`between a controlled change in the output of a voltage source, and a reaction
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`to a change in impedance. If the impedance drops so fast that the voltage
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`source cannot maintain the voltage at its target level, the voltage output by
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`the source can drop due to limitations of the voltage source. This drop in
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`voltage is not a controlled drop, caused by the power supply in response to a
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`programmed change in the voltage set point: It is a transient drop caused by
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`a change in the impedance load that exceeds the capacity of the voltage
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`source.
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`E. Magnetron Sputtering History and Operation
`47. Since the late 1970s, DC magnetron sputtering has become the
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`preferred method for the deposition of thin metal films for many
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`applications, including semiconductor devices and protective layers on
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`cutting tools.
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` Several significant advantages of this method over
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`alternatives, such as thermal evaporation or diode sputter deposition, are
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`higher deposition rate and improved film structure.
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`48. The higher deposition rate is possible because the closed loop
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`magnetic field of the magnetron traps the secondary electrons (produced
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`when the inert gas ions bombard the metal target that is attached to the
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`cathode assembly held at a negative voltage of several hundreds of volts).
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`These electrons gain energy as they are accelerated across the dark space.
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`Since most of the voltage drop from anode to cathode occurs in this region,
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`the electrons arrive in the discharge region with more than enough energy to
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`ionize the neutral gas atoms there. The crossed electric and magnetic fields
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`create a force on the electrons that causes them to circulate in a path that
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`follows the shape of the magnetic loop and is only a few mm from the face
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`of the target. The circulating current in this loop is about 10x the anode-
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`cathode current of the sputtering discharge. It is these electrons that collide
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`with, and create large numbers of ions of, the inert neutral sputtering gas
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`atoms (usually argon) that have diffused into this region. The ions are
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`accelerated toward the t