`U.S. Patent No. 6,853,142
`
`
`References cited herein:
` U.S. Pat. No. 6,853,142 (“’142 Patent”)
`
` 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”)
`
` U.S. Pat. No. 6,190,512 (“Lantsman”)
`
` D.V. Mozgrin, High-Current Low-Pressure Quasi-Stationary Discharge in a Magnetic
`Field: Experimental Research, Thesis at Moscow Engineering Physics Institute, 1994
`(“Mozgrin Thesis”)
`
` Dennis M. Manos & Daniel L. Flamm, Plasma Etching: An Introduction, Academic Press
`1989 (“Manos”)
`
` Milton Ohring, The Material Science of Thin Films, Academic Press, 1992 (“Ohring”)
`
` Donald L. Smith, Thin-Film Deposition: Principles & Practice, McGraw Hill, 1995
`(“Smith”)
`
` Yu. P. Raizer, Gas Discharge Physics, Springer, 1991 (“Raizer”)
`
`
`
`‘142 Claims 13 and 16
`
`Mozgrin in view of Lantsman and Mozgrin Thesis
`
`[10pre.] A method for
`generating a strongly-ionized
`plasma in a chamber, the
`method comprising:
`
`The combination of Mozgrin and Lantsman discloses a method
`for generating a strongly-ionized plasma in a chamber.
`
`‘142 Patent at claim 18 (“wherein the peak plasma density of
`the strongly-ionized plasma is greater than about 1012 cm˗3”)
`
`Mozgrin at Fig 1
`
`Mozgrin at 400, right col, ¶ 4 (“To study the high-current
`forms of the discharge, we used two types of devices: a planar
`magnetron and a ystem with specifically shaped hollow
`electrodes.”)
`
`Mozgrin at 401, right col, ¶2 (“For pre-ionization … the initial
`plasma 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-3).”)
`
`Mozgrin at 409, left col, ¶5 (“The high-current diffuse
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`EXHIBIT D.05
`U.S. Patent No. 6,853,142
`
`‘142 Claims 13 and 16
`
`Mozgrin in view of Lantsman and Mozgrin Thesis
`
`
`
`[10a.] ionizing a feed gas to
`form a weakly-ionized
`plasma that reduces the
`probability of developing an
`electrical breakdown
`condition in the chamber;
`
`discharge (regime 3) is useful for producing large-volume
`uniform dense plasmas ni 1.5x1015cm-3…”).
`
`The combination of Mozgrin and Lantsman discloses ionizing
`a feed gas to form a weakly-ionized plasma that reduces the
`probability of developing an electrical breakdown condition in
`the chamber.
`
`‘142 Patent at 5:18-19 (“The weakly-ionized plasma is also
`referred to as a pre-ionized plasma.”)
`
`‘142 Patent at claim 17 (“wherein the peak plasma density of
`the weakly-ionized plasma is less than about 1012 cm˗3”)
`
`Mozgrin at Figs. 1, 2, 3, 6, 7
`
`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˗3 range.”)
`
`Mozgrin at 400, right col, ¶ 3 (“We investigated the discharge
`regimes in various gas mixtures at 10-3 – 10 torr…”)
`
`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 401, left col, ¶ 1 (“The [plasma] discharge had an
`annular shape and was adjacent to the cathode.”)
`
`Mozgrin at 406, right col, ¶3 (“pre-ionization was not
`necessary; however, in this case, the probability of discharge
`transferring to arc mode increased.”)
`
`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.”)
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`EXHIBIT D.05
`U.S. Patent No. 6,853,142
`
`‘142 Claims 13 and 16
`
`Mozgrin in view of Lantsman and Mozgrin Thesis
`
`
`
`Background:
`
`Manos at 231 (“We shall … [include] information on unipolar
`arcs. These are a problem…”)
`
`Manos at 237 (“When such an arc occurs, the metal object is
`melted at the arc spot. The metal is explosively released….
`How does one prevent such an arc? There are several
`methods…”)
`
`The combination of Mozgrin and Lantsman discloses
`supplying power to the weakly-ionized plasma by applying an
`electrical pulse across the weakly-ionized plasma, the
`electrical pulse having a magnitude and a rise-time that is
`sufficient to increase the density of the weakly-ionized plasma
`to generate a strongly-ionized plasma.
`
`‘142 Patent at 1:41-43 (“Magnetron sputtering systems use
`magnetic fields that are shaped to trap and to concentrate
`secondary electrons, which are produced by ion bombardment
`of the target surface.”)
`
`‘142 Patent at 1:37-40 (“The plasma is replenished by
`electron-ion pairs formed by the collision of neutral molecules
`with secondary electrons generated at the target surface.”)
`
`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…”)
`
`The combination of Mozgrin and Lantsman discloses diffusing
`the strongly-ionized plasma with additional feed gas thereby
`allowing the strongly-ionized plasma to absorb additional
`energy from the power supply.
`
`It would have been obvious to one of ordinary skill to continue
`to add the feed gas in Mozgrin during production of the
`strongly-ionized plasma (i.e., during either of regions 2 or 3).
`Such addition of the feed gas would have both diffused the
`
`[10b.] supplying power to
`the weakly-ionized plasma
`by applying an electrical
`pulse across the weakly-
`ionized plasma, the electrical
`pulse having a magnitude
`and a rise-time that is
`sufficient to increase the
`density of the weakly-
`ionized plasma to generate a
`strongly-ionized plasma; and
`
`[10c.] diffusing the strongly-
`ionized plasma with
`additional feed gas thereby
`allowing the strongly-ionized
`plasma to absorb additional
`energy from the power
`supply.
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`EXHIBIT D.05
`U.S. Patent No. 6,853,142
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`‘142 Claims 13 and 16
`
`Mozgrin in view of Lantsman and Mozgrin Thesis
`
`
`
`strongly-ionized plasma and allowed additional power from
`Mozgrin’s repeating voltage pulses to be absorbed by the
`strongly-ionized plasma.
`
`‘142 Patent at 2:21-34 (“FIG. 1 illustrates a cross-sectional
`view of a known plasma generating apparatus 100…. A feed
`gas from feed gas source 109, such as an argon gas source, is
`introduced into the vacuum chamber 104 through a gas inlet
`110. The gas flow is controlled by a valve 112.”)
`
`Mozgrin at Figs. 1 and 3
`
`Mozgrin at ¶ spanning pp. 403-404 (“The … repetition
`frequency was 10 Hz….”).
`
`Mozgrin at 401, left col, ¶ 4 (“[A]pplying a square voltage
`pulse to the discharge gap which was filled up with either
`neutral or pre-ionized gas.”)
`
`Lantsman at Fig. 6
`
`
`
`
`Lantsman at 3:9-13 (“[A]t the beginning of processing, this
`switch is closed and gas is introduced into the chamber. When
`the plasma process is completed, the gas flow is stopped….”)
`
`Lantsman at 4:36-38 (“To end processing, primary supply 10
`is disabled, reducing the plasma current and deposition on the
`wafer. Then, gas flow is terminated….”)
`
`Lantsman at 5:39-42 (“Sometime thereafter, gas flow is
`initiated and the gas flow and pressure (trace 48) begin to ramp
`upwards toward normal processing levels.”)
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`EXHIBIT D.05
`U.S. Patent No. 6,853,142
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`‘142 Claims 13 and 16
`
`Mozgrin in view of Lantsman and Mozgrin Thesis
`
`
`
`
`Lantsman at 5:42-45
`
`Lantsman at 2:48-51 (“This secondary power supply ‘pre-
`ignites’ the plasma so that when the primary power supply is
`applied, the system smoothly transitions to final plasma
`development and deposition.”)
`
`It would have been obvious to one of ordinary skill to continue
`to apply the feed gas during Mozgrin’s regions 1 and 2 as
`taught by Lantsman. Such a continuous introduction of feed
`gas balances gas withdrawn by the vacuum system (e.g., as
`shown in the drawings from Ohring and Smith, copied below)
`so as to maintain a desired pressure.
`
`One of ordinary skill would have been motivated to combine
`Mozgrin and Lantsman. Both Mozgrin and Lantsman are
`directed to sputtering using plasma. See Mozgrin at 409, left
`col, ¶ 4 (“The implementation of the high-current magnetron
`discharge (regime 2) in sputtering or layer-deposition
`technologies provides an enhancement in the flux of deposited
`materials and plasma density….”); see also Lantsman at 1:6-8
`(“This invention relates to reduction of device damage in
`plasma processes, including DC (magnetron or non-
`magnetron) sputtering, and RF sputtering.”). Both references
`also relate to sputtering systems that use two power supplies,
`one for pre-ionization and one for deposition. See Lantsman at
`4:45-47 (“[T]he secondary [power] supply 32 is used to pre-
`ignite the plasma, whereas the primary [power] supply 10 is
`used to generate deposition.”); see Mozgrin at Fig. 2. (showing
`the “high-voltage supply unit” and the “stationary discharge
`supply unit”)
`
`Moreover, both Mozgrin and Lantsman are concerned with
`generating plasma while avoiding arcing. See Mozgrin at 400,
`right col, ¶ 3 (“The main purpose of this work was to study
`experimentally a high-power noncontracted quasi-stationary
`discharge in crossed fields of various geometry and to
`determine their parameter ranges.”); see also Lantsman at
`1:51-59 (“Furthermore, arcing which can be produced by
`overvoltages can cause local overheating of the target, leading
`to evaporation or flaking of target material into the processing
`chamber and causing substrate particle contamination and
`device damage…. Thus, it is advantageous to avoid voltage
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`EXHIBIT D.05
`U.S. Patent No. 6,853,142
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`‘142 Claims 13 and 16
`
`Mozgrin in view of Lantsman and Mozgrin Thesis
`
`
`
`spikes during processing whenever possible.”).
`
`Summarizing, Mozgrin and Lantsman relate to the same
`application. Further, one of ordinary skill would have been
`motivated to use Lantsman’s continuous gas flow in Mozgrin
`so as to maintain a desired pressure in the chamber. Finally,
`use of Lantsman’s continuous gas flow in Mozgrin would have
`been a combination of old elements in which each element
`behaved as expected. The combination of Mozgrin and
`Lantsman therefore teaches the function required by the
`“means for diffusing…”
`
`Background:
`Ohring at Fig. 3-13
`
`Smith at Fig. 3-1
`
`
`
`13. The method of claim 10
`wherein the applying the
`electrical pulse comprises
`applying a quasi-static
`electric field across the
`weakly-ionized plasma.
`
`
`The combination of Mozgrin, Lantsman, and the Mozgrin
`Thesis discloses wherein the applying the electrical pulse
`comprises applying a quasi-static electric field across the
`weakly-ionized plasma.
`
`See evidence cited in claim 10.
`
`‘142 Patent, 7:16-19 (“In another embodiment, the electric
`field 236 is a quasi –static electric field. By quasi-static
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`EXHIBIT D.05
`U.S. Patent No. 6,853,142
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`‘142 Claims 13 and 16
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`Mozgrin in view of Lantsman and Mozgrin Thesis
`
`
`
`electric field we mean an electric field that has a characteristic
`time of electric field variation that is much greater than the
`collision time for electrons with neutral gas particles.”)
`
`Mozgrin at pp. 407-8, Tables 1 and 2 (“0.1 Torr”)
`
`For 0.1 Torr, a pressure in Mozgrin’s disclosed range, the
`collision frequency is 0.53 x 109 s-1 (i.e., (5.3 x 109 s-1
`Torr-1)x(0.1 Torr) = 0.53 x 109 s-1). Therefore, Mozgrin’s
`collision time was therefore approximately 1.88 nanoseconds
`( 1/0.53x109 s).
`
`Mozgrin, at 402, Fig. 3 caption, (“Fig. 3. Oscillograms of
`…(50 µs per div., …”)
`
`Mozgrin Thesis at Fig. 3.2
`
`
`It would have been obvious for one of ordinary skill to
`combine Mozgrin and Lantsman with the Mozgrin Thesis.
`Both Mozgrin and Mozgrin Thesis are written by the same
`author, address similar subject matter, and describe the same
`research. The Mozgrin Thesis merely provides additional
`detail for the material already disclosed in Mozgrin. Thus, a
`person of ordinary skill would have combined the Mozgrin
`Thesis with Mozgrin to add additional details not present in
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`EXHIBIT D.05
`U.S. Patent No. 6,853,142
`
`‘142 Claims 13 and 16
`
`Mozgrin in view of Lantsman and Mozgrin Thesis
`
`
`
`16. The method of claim 10
`wherein the electrical pulse
`comprises a rise time that is
`less than about 100V/µsec.
`
`Mozgrin.
`
`Background:
`
`Raizer at 11, §2.1.4, (“The collision frequency m is
`proportional to…pressure p.”).
`
`Raizer at Table 2.1 (“m/p = 5.3 x 109 s-1 Torr-1.”)
`
`The combination of Mozgrin, Lantsman, and the Mozgrin
`Thesis discloses the electrical pulse comprises a rise time that
`is less than about 100V/µsec.
`
`See evidence cited in claim 10.
`
`Mozgrin at Fig. 3
`
`Mozgrin, at 402, Fig. 3 caption, (“Fig. 3. Oscillograms of
`…(50 µs per div., … 180 V per div”)
`
`Mozgrin Thesis at Fig. 3.2
`
`
`
`The peak voltage in region 2 is about 720 V ( 4 div x 180
`V/div) and the voltage in region 1 is about 360 V ( 2 div x
`180 V/div). This difference is about 360 V.
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`EXHIBIT D.05
`U.S. Patent No. 6,853,142
`
`‘142 Claims 13 and 16
`
`Mozgrin in view of Lantsman and Mozgrin Thesis
`
`Mozgrin at 401, right col, ¶ 1 (“…the supply unit was made
`providing square voltage and current pulses with [rise] times
`(leading edge) of 5 – 60 µs...”)
`
`Assuming Mozgrin utilized the fastest rise of the leading edge
`(i.e., 5 µs) for the pulse shown in Fig 3 of Mozgrin (Fig. 3.2 of
`Mozgrin Thesis), Mozgrin discloses a rise time of about 72
`V/µs (i.e., 360Volts/5µs = 72 V/µs). Even if Mozgrin utilized
`the slowest rise of the leading edge (i.e., 60 µs, which would
`exceed a single division on the oscillogram), Mozgrin would
`have nevertheless achieved a rise time of 1.2 V/µs (i.e., 360
`Volts/60µs = 1.2 V/µs).
`
`
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