`U.S. Patent No. 7,147,759
`
`References cited herein:
`
`(cid:120) U.S. Patent No. 7,147,759 (“‘759 Patent”)
`
`(cid:120) D.V. Mozgrin, et al, High-Current Low-Pressure Quasi-Stationary Discharge in a
`Magnetic Field: Experimental Research, Plasma Physics Reports, Vol. 21, No. 5, 1995
`(“Mozgrin”)
`
`(cid:120) A. A. Kudryavtsev, et al, Ionization relaxation in a plasma produced by a pulsed inert-gas
`discharge, Sov. Phys. Tech. Phys. 28(1), January 1983 (“Kudryavtsev”)
`
`(cid:120) U.S. Pat. No. 5,247,531 (“Muller-Horsche”)
`
`Claims 17 and 39
`[1pre.] A
`magnetically
`enhanced sputtering
`source comprising:
`
`Mozgrin in view of Kudryavtsev and Muller-Horsche
`
`The combination of Mozgrin with Kudryavtsev discloses a
`magnetically enhanced sputtering source.
`Mozgrin 403, right col, ¶4 (“Regime 2 was characterized by intense
`cathode sputtering…”)
`Mozgrin at Fig. 1
`
`
`
`
`
`[1a.] an anode;
`
`The combination of Mozgrin with Kudryavtsev discloses an anode.
`‘759 Patent at Fig. 1
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`EXHIBIT A.04
`U.S. Patent No. 7,147,759
`
`Claims 17 and 39
`
`Mozgrin in view of Kudryavtsev and Muller-Horsche
`
`
`‘759 Patent at Fig. 1 (“FIG. 1 illustrates a cross-sectional view of a
`known magnetron sputtering apparatus having a pulsed power source.”)
`‘759 Patent at 3:40-41 (“an anode 130 is positioned in the vacuum
`chamber 104 proximate to the cathode assembly.”)
`Mozgrin at Fig. 1
`
`[1b.] a cathode
`
`The combination of Mozgrin with Kudryavtsev discloses a cathode
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`Mozgrin in view of Kudryavtsev and Muller-Horsche
`
`assembly that is positioned adjacent to the anode, the cathode assembly
`including a sputtering target.
`‘759 Patent at Fig. 1
`
`Claims 17 and 39
`assembly that is
`positioned adjacent
`to the anode, the
`cathode assembly
`including a
`sputtering target;
`
`
`
`‘759 Patent at 3:10-12 (“FIG. 1 illustrates a cross-sectional view of a
`known magnetron sputtering apparatus having a pulsed power source.”)
`‘759 Patent at 3:23-24 (“magnetron sputtering apparatus 100 also
`includes a cathode assembly 114 having a target material 116.”)
`Mozgrin at 403, right col, ¶ 4 (“Regime 2 was characterized by intense
`cathode sputtering…”).
`Mozgrin at 403, right col, ¶ 4 (“…The pulsed deposition rate of the
`cathode material…”).
`Mozgrin at Fig. 1
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`
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`EXHIBIT A.04
`U.S. Patent No. 7,147,759
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`Claims 17 and 39
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`Mozgrin in view of Kudryavtsev and Muller-Horsche
`
`[1c.] an ionization
`source that
`generates a weakly-
`ionized plasma
`proximate to the
`anode and the
`cathode assembly;
`
`
`
`The combination of Mozgrin with Kudryavtsev discloses an ionization
`source that generates a weakly-ionized plasma proximate to the anode
`and the cathode assembly.
`‘759 Patent at 6:30-32 (“The weakly-ionized plasma is also referred to
`as a pre-ionized plasma.”)
`‘759 Patent at claim 32 (“wherein the peak plasma density of the
`weakly-ionized plasma is less than about 1012 cm(cid:1956)3”).
`Mozgrin at 401, right col, ¶2 (“For pre-ionization, we used a stationary
`magnetron discharge; the discharge current ranged up to 300 mA….
`We found out that only the regimes with magnetic field strength not
`lower than 400 G provided the initial plasma density in the 109 – 1011
`cm-3 range.”). (emphasis added).
`Mozgrin at 401, left col, ¶ 1 (“The [plasma] discharge had an annular
`shape and was adjacent to the cathode.”). (emphasis added)
`Mozgrin at 402, right col, ¶2 (“Figure 3 shows typical voltage and
`current oscillograms.… Part I in the voltage oscillogram represents the
`voltage of the stationary discharge (pre-ionization stage).”).
`Mozgrin at Fig. 6
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`U.S. Patent No. 7,147,759
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`Claims 17 and 39
`
`Mozgrin in view of Kudryavtsev and Muller-Horsche
`
`[1d.] a magnet that
`is positioned to
`generate a magnetic
`field proximate to
`the weakly-ionized
`plasma, the
`magnetic field
`substantially
`trapping electrons in
`the weakly-ionized
`plasma proximate to
`the sputtering target;
`and
`
`
`
`The combination of Mozgrin with Kudryavtsev discloses a magnet that
`is positioned to generate a magnetic field proximate to the weakly-
`ionized plasma, the magnetic field substantially trapping electrons in
`the weakly-ionized plasma proximate to the sputtering target.
`‘759 Patent at 3:10-12 (“FIG. 1 shows a cross-sectional view of a
`known magnetron sputtering apparatus 100…” that has a magnet 126.”)
`‘759 Patent at 4:4-10 [describing the prior art Fig. 1] (“The electrons,
`which cause ionization, are generally confined by the magnetic fields
`produced by the magnet 126. The magnetic confinement is strongest in
`a confinement region 142….”)
`Mozgrin at 401, left col, ¶ 1 (“The electrodes were immersed in a
`magnetic field of annular permanent magnets.”).
`Mozgrin at 401, right col, ¶2 (“We found out that only the regimes with
`magnetic field strength not lower than 400 G provided the initial
`plasma density in the 109-1011 cm-3 range.”).
`Mozgrin at 407, left col, ¶ 3 (“The action of the magnetic field serves
`only to limit the electron thermal conductivity and to provide collisions
`sufficient for efficient energy transfer from electrons to heavy
`particles.”).
`Mozgrin at Fig. 1
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`U.S. Patent No. 7,147,759
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`Claims 17 and 39
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`Mozgrin in view of Kudryavtsev and Muller-Horsche
`
`
`
`
`
`The combination of Mozgrin with Kudryavtsev discloses a power
`supply generating a voltage pulse that produces an electric field
`between the cathode assembly and the anode, the power supply being
`configured to generate the voltage pulse with an amplitude and a rise
`time that increases an excitation rate of ground state atoms that are
`present in the weakly-ionized plasma to create a multi-step ionization
`process that generates a strongly-ionized plasma, which comprises ions
`that sputter target material, from the weakly-ionized plasma, the multi-
`step ionization process comprising exciting the ground state atoms to
`generate excited atoms, and then ionizing the excited atoms within the
`weakly-ionized plasma without forming an arc discharge.
`
`‘759 Patent, claim 33 (“wherein the peak plasma density of the
`strongly-ionized plasma is greater than about 1012 cm(cid:1956)3”)
`Mozgrin at Fig. 1
`
`[1e.] a power supply
`generating a voltage
`pulse that produces
`an electric field
`between the cathode
`assembly and the
`anode, the power
`supply being
`configured to
`generate the voltage
`pulse with an
`amplitude and a rise
`time that increases
`an excitation rate of
`ground state atoms
`that are present in
`the weakly-ionized
`plasma to create a
`multi-step ionization
`process that
`generates a strongly-
`ionized plasma,
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`Claims 17 and 39
`which comprises
`ions that sputter
`target material, from
`the weakly-ionized
`plasma, the multi-
`step ionization
`process comprising
`exciting the ground
`state atoms to
`generate excited
`atoms, and then
`ionizing the excited
`atoms within the
`weakly-ionized
`plasma without
`forming an arc
`discharge.
`
`
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`EXHIBIT A.04
`U.S. Patent No. 7,147,759
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`Mozgrin in view of Kudryavtsev and Muller-Horsche
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`
`
`
`
`Mozgrin at Fig. 2
`
`
`
`Mozgrin at Fig. 3
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`U.S. Patent No. 7,147,759
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`Claims 17 and 39
`
`Mozgrin in view of Kudryavtsev and Muller-Horsche
`
`Mozgrin at 402, right col, ¶ 2 (“Part 1 in the voltage oscillogram
`represents the voltage of the stationary discharge (pre-ionization
`stage).”)
`Mozgrin at 401, right col, ¶ 1 (“Thus, the supply unit was made
`providing square voltage and current pulses with [rise] times (leading
`edge) of 5 – 60 μs…”).
`Mozgrin at 409, left col, ¶ 4 (“The implementation of the high-current
`magnetron discharge (regime 2) in sputtering … plasma density
`(exceeding 2x1013 cm-3).”)
`Mozgrin 403, right col, ¶4 (“Regime 2 was characterized by intense
`cathode sputtering…”)
`Mozgrin at 409, left col, ¶5 (“The high-current diffuse discharge
`(regime 3) is useful for producing large-volume uniform dense plasmas
`ni (cid:35) 1.5x1015cm-3…”)
`Mozgrin at 401, ¶ spanning left and right columns (“Designing the
`[pulsed supply] unit, we took into account the dependences which had
`been obtained in [Kudryavtsev] of ionization relaxation on pre-
`ionization parameters, pressure, and pulse voltage amplitude.”)
`Mozgrin at 400, left col, ¶ 3 (“Some experiments on magnetron systems
`of various geometry showed that discharge regimes which do not transit
`to arcs can be obtained even at high currents.”)
`Mozgrin at 400, right col, ¶ 1 (“A further increase in the discharge
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`U.S. Patent No. 7,147,759
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`Claims 17 and 39
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`Mozgrin in view of Kudryavtsev and Muller-Horsche
`
`currents caused the discharges to transit to the arc regimes…”).
`Mozgrin at 401, right col, ¶2 (“For pre-ionization … the initial plasma
`density in the 109 – 1011 cm-3 range.”)
`Mozgrin at 404, left col, ¶ 3 (“The parameters of the shaped-electrode
`discharge…transit to arc regime 4, could be well determined… The
`point of the planar-magnetron discharge transit to the arc regime was
`determined by discharge voltage and structure changes...”).
`Mozgrin at 404, left col, ¶ 4 (“If the current was raised above 1.8 kA or
`the pulse duration was increase to 2 – 10 ms, an instability development
`and discharge contraction was observed.”).
`Mozgrin at 409, left col, ¶ 4 (“The implementation of the high-current
`magnetron discharge (regime 2) in sputtering … plasma density
`(exceeding 2x1013 cm-3).”).
`Mozgrin at Fig. 4
`
`Mozgrin at Fig. 7
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`U.S. Patent No. 7,147,759
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`Claims 17 and 39
`
`Mozgrin in view of Kudryavtsev and Muller-Horsche
`
`Kudryavtsev at 34, right col, ¶ 4 (“Since the effects studied in this work
`are characteristic of ionization whenever a field is suddenly applied to a
`weakly ionized gas, they must be allowed for when studying emission
`mechanisms in pulsed gas lasers, gas breakdown, laser sparks, etc.”)
`Kudryavtsev at Fig. 1
`
`Kudryavtsev at Fig. 6
`
`Kudryavtsev at 31, right col, ¶ 7 (“The behavior of the increase in ne
`with time thus enables us to arbitrarily divide the ionization process
`into two stages, which we will call the slow and fast growth stages.
`Fig. 1 illustrates the relationships between the main electron currents in
`terms of the atomic energy levels during the slow and fast stages.”).
`Kudryavtsev at 31, right col, ¶ 6 (“For nearly stationary n2 [excited
`atom density] values … there is an explosive increase in ne [plasma
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`Claims 17 and 39
`
`Mozgrin in view of Kudryavtsev and Muller-Horsche
`
`17. The sputtering
`source of claim 1
`wherein the
`ionization source is
`chosen from the
`group comprising a
`UV source, an X-ray
`source, an electron
`beam source, and an
`ion beam source.
`
`density]. The subsequent increase in ne then reaches its maximum
`value, equal to the rate of excitation [equation omitted], which is
`several orders of magnitude greater than the ionization rate during
`the initial stage.”) (emphasis added).
`Kudryavtsev at Abstract (“[I]n a pulsed inert-gas discharge plasma at
`moderate pressures… [i]t is shown that the electron density increases
`explosively in time due to accumulation of atoms in the lowest excited
`states.”) (emphasis added).
`One of ordinary skill would have been motivated to use Kudryavtsev’s
`fast stage of ionization in Mozgrin so as to increase plasma density and
`thereby increase the sputtering rate. Further, use of Kudryavtsev’s fast
`stage in Mozgrin would have been a combination of old elements that
`in which each element performed as expected to yield predictable
`results of increasing plasma density and multi-step ionization.
`The combination of Mozgrin with Kudryavtsev and Muller-Horsche
`discloses the ionization source is chosen from the group comprising a
`UV source, an X-ray source, an electron beam source, and an ion beam
`source.
`See evidence cited in claim 1.
`Muller-Horsche at Title (“an apparatus for preionizing a pulsed gas
`laser.”)
`Muller-Horsche at 1:40-42 (“Typically, in such a preionizing relatively
`low electron concentrations (for example 107 electrons/cm3) are
`generated in the discharge space.”).
`Muller-Horsche at 2:59-63 (emphasis added) (“[electrodes 12, 12’]
`generates a corona discharge on the dielectric tubes 14, 14’. The
`corona discharge in turn emits UV radiation which preionizes the
`gas…”)
`Muller-Horsche at 1:34-36 ([preionization] “is carried out in particular
`also to avoid arc discharges.”).
`In the field of pulsed lasers, the use of pre-ionization as a means of
`avoiding arcing is common knowledge. Muller-Horsche at 1:34-36
`([preionization] “is carried out in particular also to avoid arc
`discharges.”). Further, those of ordinary skill in the field of plasma
`sputtering typically look to pulsed laser plasma references when
`studying features of plasmas such as arc avoidance. For example,
`Mozgrin, which teaches “[t]he implementation of the high-current
`magnetron discharge (regime 2) in sputtering or layer-deposition
`technologies,” Mozgrin at 409, left col., ¶ 4, “took into account the
`dependences which had been obtained in [Kudryavtsev]….” Mozgrin
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`Claims 17 and 39
`
`Mozgrin in view of Kudryavtsev and Muller-Horsche
`
`[20pre.] A method
`of generating
`sputtering flux, the
`method comprising:
`
`
`[20a.] ionizing a
`feed gas to generate
`a weakly-ionized
`plasma proximate to
`a sputtering target;
`
`
`at 401, ¶ spanning left and right cols. Kudryavtsev in turn discloses
`that “[i]nterest in ionization relaxation in inert gas discharges has been
`stimulated recently by the rapid development of excimer lasers excited
`by pulsed electrical discharges (see, e.g., Ref. 1).” Kudryavtsev at 30,
`left col, ¶ 1
`Therefore, one of ordinary skill in the art would have been motivated to
`combine the use of different ionization sources, such as those described
`by Muller-Horsche, with the teachings of Mozgrin. A combination of
`Muller-Horche’s UV source with Mozgrin would be a combination of
`known elements in which each element performed as expected.
`The combination of Mozgrin with Kudryavtsev discloses a method of
`generating sputtering flux.
`See evidence cited in limitation [1pre] of claim 1.
`Mozgrin at 403, right col, ¶ 4 (“Regime 2 was characterized by intense
`cathode sputtering…”).
`The combination of Mozgrin with Kudryavtsev discloses ionizing a
`feed gas to generate a weakly-ionized plasma proximate to a sputtering
`target.
`See evidence cited in limitation [1c] of claim 1.
`‘759 Patent at 6:30-32 (“The weakly-ionized plasma is also referred to
`as a pre-ionized plasma.”)
`‘759 Patent at claim 32 (“wherein the peak plasma density of the
`weakly-ionized plasma is less than about 1012 cm(cid:1956)3”)
`Mozgrin at Fig. 2
`Mozgrin at 402, right col, ¶2 (“Figure 3 shows typical voltage and
`current oscillograms.… Part I in the voltage oscillogram represents the
`voltage of the stationary discharge (pre-ionization stage).”)
`Mozgrin at 401, right col, ¶2 (“[f]or pre-ionization, we used a
`stationary magnetron discharge; … provided the initial plasma density
`in the 109 – 1011 cm(cid:1956)3 range.”)
`Mozgrin at 400, right col, ¶ 3 (“We investigated the discharge regimes
`in various gas mixtures at 10-3 – 10 torr…”)
`Mozgrin at 402, ¶ spanning left and right cols (“We studied the high-
`current discharge in wide ranges of discharge current…and operating
`pressure…using various gases (Ar, N2, SF6, and H2) or their mixtures of
`various composition…”)
`Mozgrin at 403, right col, ¶ 4 (“Regime 2 was characterized by intense
`cathode sputtering…”).
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`U.S. Patent No. 7,147,759
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`Mozgrin in view of Kudryavtsev and Muller-Horsche
`
`The combination of Mozgrin with Kudryavtsev discloses generating a
`magnetic field proximate to the weakly-ionized plasma, the magnetic
`field substantially trapping electrons in the weakly-ionized plasma
`proximate to the sputtering target.
`‘759 Patent at 3:10-12 (“Fig. 1 shows a cross-sectional view of a
`known magnetron sputtering apparatus 100…”)
`‘759 Patent at 4:4-10 (“The electrons, which cause ionization, are
`generally confined by the magnetic fields produced by the magnet 126.
`The magnetic confinement is strongest in a confinement region
`142….”)
`Mozgrin at 401, left col, ¶ 1 (“The electrodes were immersed in a
`magnetic field of annular permanent magnets.”)
`Mozgrin at 401, right col, ¶2 (“We found out that only the regimes with
`magnetic field strength not lower than 400 G provided the initial
`plasma density in the 109-1011 cm-3 range.”)
`Mozgrin at 407, left col, ¶ 3 (“The action of the magnetic field serves
`only to limit the electron thermal conductivity and to provide collisions
`sufficient for efficient energy transfer from electrons to heavy
`particles.”)
`The combination of Mozgrin with Kudryavtsev discloses applying a
`voltage pulse to the weakly-ionized plasma, an amplitude and a rise
`time of the voltage pulse being chosen to increase an excitation rate of
`ground state atoms that are present in the weakly-ionized plasma to
`create a multi-step ionization process that generates a strongly-ionized
`plasma, which comprises ions that sputter target material, from the
`weakly-ionized plasma, the multi-step ionization process comprising
`exciting the ground state atoms to generate excited atoms, and then
`ionizing the excited atoms within the weakly-ionized plasma without
`forming an arc discharge.
`‘759 Patent, claim 33 (“wherein the peak plasma density of the
`strongly-ionized plasma is greater than about 1012 cm(cid:1956)3”)
`Mozgrin at Figs. 1, 2, 3
`Mozgrin at 402, right col, ¶ 2 (“Part 1 in the voltage oscillogram
`represents the voltage of the stationary discharge (pre-ionization
`stage).”)
`Mozgrin at 401, right col, ¶ 1 (“Thus, the supply unit was made
`providing square voltage and current pulses with [rise] times (leading
`edge) of 5 – 60 μs…”)
`Mozgrin at 401, right col, ¶2 (“For pre-ionization … the initial plasma
`
`Claims 17 and 39
`[20b.] generating a
`magnetic field
`proximate to the
`weakly-ionized
`plasma, the
`magnetic field
`substantially
`trapping electrons in
`the weakly-ionized
`plasma proximate to
`the sputtering target;
`and
`
`
`[20c.] applying a
`voltage pulse to the
`weakly-ionized
`plasma, an
`amplitude and a rise
`time of the voltage
`pulse being chosen
`to increase an
`excitation rate of
`ground state atoms
`that are present in
`the weakly-ionized
`plasma to create a
`multi-step ionization
`process that
`generates a strongly-
`ionized plasma,
`which comprises
`ions that sputter
`target material, from
`the weakly-ionized
`plasma, the multi-
`step ionization
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`Claims 17 and 39
`process comprising
`exciting the ground
`state atoms to
`generate excited
`atoms, and then
`ionizing the excited
`atoms within the
`weakly-ionized
`plasma without
`forming an arc
`discharge.
`
`
`EXHIBIT A.04
`U.S. Patent No. 7,147,759
`
`Mozgrin in view of Kudryavtsev and Muller-Horsche
`
`density in the 109 – 1011 cm-3 range.”)
`Mozgrin at 409, left col, ¶ 4 (“The implementation of the high-current
`magnetron discharge (regime 2) in sputtering … plasma density
`(exceeding 2x1013 cm(cid:1956)3).”)
`Mozgrin at 403, right col, ¶4 (“Regime 2 was characterized by intense
`cathode sputtering…”)
`Mozgrin at 401, ¶ spanning left and right columns (“Designing the
`[pulsed supply] unit, we took into account the dependences which had
`been obtained in [Kudryavtsev] of ionization relaxation on pre-
`ionization parameters, pressure, and pulse voltage amplitude.”)
`Mozgrin at 400, left col, ¶ 3 (“Some experiments on magnetron systems
`of various geometry showed that discharge regimes which do not transit
`to arcs can be obtained even at high currents.”)
`Mozgrin at 404, left col, ¶ 3 (“The parameters of the shaped-electrode
`discharge…transit to arc regime 4, could be well determined… The
`point of the planar-magnetron discharge transit to the arc regime was
`determined by discharge voltage and structure changes...”)
`Kudryavtsev at Figs. 1, 6
`Kudryavtsev at 34, right col, ¶ 4 (“Since the effects studied in this work
`are characteristic of ionization whenever a field is suddenly applied to a
`weakly ionized gas, they must be allowed for when studying emission
`mechanisms in pulsed gas lasers, gas breakdown, laser sparks, etc.”)
`Kudryavtsev at 31, right col, ¶ 7 (“The behavior of the increase in ne
`with time thus enables us to arbitrarily divide the ionization process
`into two stages, which we will call the slow and fast growth stages.
`Fig. 1 illustrates the relationships between the main electron currents in
`terms of the atomic energy levels during the slow and fast stages.”)
`Kudryavtsev at 31, right col, ¶ 6 (“For nearly stationary n2 [excited
`atom density] values … there is an explosive increase in ne [plasma
`density]. The subsequent increase in ne then reaches its maximum
`value, equal to the rate of excitation [equation omitted], which is
`several orders of magnitude greater than the ionization rate during
`the initial stage.”)
`Because Mozgrin applies voltage pulses that “suddenly generate an
`electric field,” one of ordinary skill reading Mozgrin would have been
`motivated to consider Kudryavtsev to better understand the effects of
`applying Mozgrin’s pulse.
`If one of ordinary skill building a system according to Mozgrin did not
`experience Kudryavtsev’s “explosive increase” in plasma density, it
`would have been obvious to adjust the operating parameters, e.g.,
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`U.S. Patent No. 7,147,759
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`Claims 17 and 39
`
`Mozgrin in view of Kudryavtsev and Muller-Horsche
`
`increase the pulse length and/or pressure, so as to trigger Kudryavtsev’s
`fast stage of ionization. One of ordinary skill would have been
`motivated to use Kudryavtsev’s fast stage of ionization in Mozgrin so
`as to increase plasma density and thereby increase the sputtering rate.
`Further, use of Kudryavtsev’s fast stage in Mozgrin would have been a
`combination of old elements that in which each element performed as
`expected to yield predictable results of increasing plasma density and
`multi-step ionization. Finally, because Mozgrin’s pulse, or the pulse
`used in the combination of Mozgrin and Kudryavtsev, produced
`Kudryavtsev’s fast stage of ionization, the rise time and amplitude of
`the pulse result in increasing the ionization rate of excited atoms and
`creation of a multi-step ionization process.
`The combination of Mozgrin with Kudryavtsev and Muller-Horsche
`discloses the ionizing the feed gas comprises exposing the feed gas to at
`least one of a UV source, an X-ray source, an electron beam source,
`and an ion beam source.
`See evidence cited in 20.
`See evidence cited in 17.
`
`
`39. The method of
`claim 20 wherein
`the ionizing the feed
`gas comprises
`exposing the feed
`gas to at least one of
`a UV source, an X-
`ray source, an
`electron beam
`source, and an ion
`beam source.
`
`
`
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