`Case 6:20-cv-00636—ADA Document 78 Filed 03/10/21 Page 1 of 9
`
`EXHIBIT 12
`
`EXHIBIT 12
`
`
`
`Case 6:20-cv-00636-ADA Document 78 Filed 03/10/21 Page 2 of 9
`ADVANCED
`ENERGY")
`
`By John Harpold and Richard A. Scholl of Advanced Energy Industries, Inc.
`
`HOW ADVANCED
`ENERGY, MOX™
`PRODUCTS MANAGE
`
`ARCS
`
`AU MDX products have been engineered not only to survive the severe
`environment of vacuum arcs, but also to provide a high level of arc control for the
`purpose of minimizing arc-related damage. Arc-related damage can be divided into three
`categories:
`• Damage to deposition targets, which is generally heat related
`• Contamination of the film resulting from foreign particles or target material particulates
`contacting the film and being included in it
`• Damage to growing films, caused by arcs striking or moving across the film surface
`Although the use of an MDX power supply can greatly reduce the possibility of vacuum
`chamber arcing, two specific electronic circuits in the MDX are designed to minimize the destructive
`effects of arcs that do occur. These trademarked circuits are ARC-OlJTTM and ARC-CHECI(fM.
`
`ARC-OUT™
`ARC-OUT consists of a passive and an active circuit.
`The passive circuit is designed to control the energy level and
`the duration of small arcs. The active circuit comes into play
`when the arc is too large to extinguish with the passive circuit.
`This active part of ARC-OUT also protects the power supply
`from destructive high current levels resulting from short circuits.
`
`The passive part of ARC-OUT that controls small arcs
`consists primarily of an inductor and capacitor that fom1 a
`resonant circuit. When an arc occurs in the chamber, the
`resulting lowered impedance across the output of the power
`supply permits the energy in the capacitor to be transferred to
`the inductor and then back again to the capacitor. The resulting
`oscillatory (ringing) waveform of current can cause the plasma
`current to actually reverse in polarity momentarily. This means
`
`Microseconds
`
`Milliseconds
`
`0
`
`10 20 30
`
`5
`
`10
`
`15
`
`I
`I
`I
`
`I
`I
`I
`I
`--1
`
`0
`
`0
`
`200
`
`20
`
`400
`
`40
`
`600
`
`60
`
`I L Current
`
`---
`
`,.
`
`~-,
`'
`' '
`
`/
`
`/
`
`/
`
`I
`
`.... __ J
`
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`0
`
`"'
`"' II
`
`C.
`E
`u
`""
`<
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`I
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`I
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`CO I
`111
`-1
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`>1 /
`
`-
`
`\
`
`S1 ' .... / ..... ,.,,...,,.. .... '- _
`~I /
`..,, ,
`t:'.'1
`v=,1,
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`0
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`Figure 1. The passive circuit of ARC-OUT attempts unsuccessfully to quench
`a chamber arc. The active circuit of ARC-OUT intervenes to successfully
`quench the arc.
`
`that instead of supplying
`current to the load (and the
`arc), the MDX will temporarily
`draw current (electrons) from the
`load (Figure 1). This reversal will
`occur if the process voltage is above
`a certain minimum, the process
`current does not exceed a certain
`maximum, and the impedance of the
`arc is low enough. For most processes
`and arcs these conditions are met and
`the current will reverse.
`If the resonant circuit is able to reverse
`the current direction, the voltage of the
`load will go to zero {or even reverse slightly
`to positive) and the arc will be extinguished.
`This will happen in about 10 µs, and the
`process will continue without further
`interruption. It is important to note that the
`plasma in the chamber will not be extinguished,
`even though the voltage goes briefly to zero.
`Because the change happens so quickly, the ions do
`not have time to diffuse to the chamber walls, and
`the plasma does not need to be reignited. Because
`the arc is limited in both current and duration , any
`resultant damage is kept to a low level. Well over 95%
`of the arcs nom1ally encountered in plasma processing
`are extinguished by this ringing circuit, and it is important
`to note that very little ( well under 10%) of the energy
`stored in the power supply's output circuits is delivered to
`the arc in this case.
`If the conditions for current reversal are not met, the load
`voltage will not reverse, and the arc will not be extinguished.
`In this case, the output circuits of the power supply will
`continue to drive current into the arc, and the second part of
`the ARC-OUT circuit must be activated.
`
`1
`
`
`
`Case 6:20-cv-00636-ADA Document 78 Filed 03/10/21 Page 3 of 9
`
`HOW ADVANCED ENERGY, MDX™ PRODUCTS MANAGE ARCS
`
`The arc represents a low impedance across the power
`supply. If the ringing circuit described above is not successful,
`the arc will draw more and more current from the MDX.
`The active ARC-OUT circuit senses this rapid increase in
`current and tums off the switching transistors in the MDX. This
`happens in a few tens of microseconds. Once the MDX is shut
`off in this way, the output filter components can bleed off their
`stored energy, and the output voltage can go to zero. When this
`happens, both the arc and the plasma will be extinguished. This
`happens in about 5 ms. The logic in ARC-OUT will keep the
`output off for an additional 3-5 ms to allow for cooling of the
`arc site, reducing the chances of anoth er arc at startup. In 8-10
`ms after the shut down, the output will be enabled and the
`process will resume. This rapid shutdown, in addition to the use
`of small filter components in the output section (lowering
`stored energy), reduces the damaging effects of the arc.
`
`An improved version of the ARCOUT circuit is available
`on the MDX domestic and international voltage units as an
`option. This option is referred to as the enhanced version of
`ARC-OUT. In the enhanced version, the passive circuit has
`been changed so that the latitude for output current reversal is
`wider. This means that fewer arcs will result in a power supply
`tumoff.
`
`ARC-CHECK™
`ARC-CHECK is an active circuit in the MDX that is
`useful in establishing a bias voltage in cathodic arc processes
`and in buming away target flakes that create cathode-to-anode
`shorts in magnetrons. ARC-CHECK is available as an option
`on the MDX domestic voltage, international voltage, and
`MDXII products.
`
`In cathodic arc deposition processes, current supplies
`drive an arc discharge on a metal cathode target to vaporize the
`target material. This vaporized target material is deposited on a
`substrate as a hard or decorative coating. Vaporized metal atoms
`are ionized ( +) in the arc discharge upon leaving the cathode by
`removal of one or two electrons. An MDX supply can be used
`to create a negative voltage (bias) on the substrates to be
`coated. This bias voltage (-) will attract the metal ions ( +) to
`speed up film growth and enable coatings in non-line-of-sight
`locations (Figure 2).
`If arc supplies are pem1itted to run while the bias supply is
`off, such as when ARC-OUT has shut off the output of d1e
`MDX for 8-10 ms to extinguish a chamber arc, the chamber
`can become saturated with ions. This produces a very low
`impedance load for ilie MDX that, like an arc, causes high
`enough current levels to trip d,e active ARC-OUT circuit
`again. This cycle can continue, disabling d,e process (Figure 3 ).
`
`ARC-CHECK will sense this cycle and intervene. The MDX
`will temporarily be changed from voltage regulation mode to
`
`2
`
`+
`
`~I ~~
`l -
`1 Source
`\
`
`DC
`Arc
`
`Process~~--_,,
`Gas
`
`" - - -.,-
`
`To Vacuum
`Pump
`
`MDX
`Voltage
`Bias
`
`+
`
`Figure 2. A vacuum system for executing cathodic arc depositions
`
`current regulation mode, and the output will be ran,ped up to the
`programmed level, starting at O A. As the current is incre..1Sed,
`ions are drawn to the substrate, and an unsaturated condition is
`restored in ilie chamber. Once the desired substrate voltage is
`achieved in current regulation mode, ARC-CHECK restores the
`MDX to voltage regulation mode and ilie process continues.
`
`A similar cycle can result in a sputtering process when a
`flake of target material becomes lodged between d1e cathode
`and anode of the magnetron. The shorting flake cannot be
`melted away because of the fast reaction time of ilie active
`ARCOUT circuit and the small amount of energy stored in
`the MDX output. Again ARC-CHECK can intervene to
`temporarily change d1e MDX to current regulation mode and
`ran,p me current up w1til the flake is melted away and d1e
`normal power level restored. Advanced Energy Industries, Inc.,
`holds design and process patents on ARC-CHECK.
`
`SPARC·LE8
`Small Package Arc Repression Circuit-Low Energy is the
`name of an accessory product that offers new ways to manage
`chamber arcs. Spare-le is designed for use with any MDX unit
`with 2.5 kW to 10 kW output, with a maximwn of 25 A.
`A larger version, Spare, is designed for use on MDX units from
`10 kW to 30 kW, wiili a maximum process current of 100 A
`(Figure 4).
`
`
`
`Case 6:20-cv-00636-ADA Document 78 Filed 03/10/21 Page 4 of 9
`
`HOW ADVANCED ENERGY, MDX™ PRODUCTS MANAGE ARCS
`
`O
`
`100
`
`200
`
`300
`
`400
`
`500
`
`Milliseconds
`600
`700 800
`
`900 1000 1100 1200 1300
`
`5
`
`"' a.
`~ 10
`8
`
`15
`
`20
`
`Multiple arc
`trip cycles
`
`550
`Variable
`ramp to
`full current
`
`600
`Variable
`"out-of-setpoint"
`shutdown
`
`Figure 3. ARC-CHECK circuits will drive high current levels into the load to
`increase the load impedance or melt cathode-to-anode flake shorts.
`
`~Arc event
`
`oV
`
`-400V
`
`I
`I
`
`J
`
`- '
`
`\
`\
`' ~
`
`Time (4 µS/div)
`
`~Arc event
`
`oA
`
`-20A
`
`-6oA
`
`-
`
`\
`
`J
`I
`I
`
`\
`
`\
`
`\J
`
`Time (4 µS / div)
`Figure 5. The voltage and current waveform of Spare-le quenching an arc in
`ARC-OUT enhancement mode
`
`energy to bum away burrs but not enough energy to damage
`targets. Since iliis mode of operation does not interrupt the
`conditioning process or extinguish d1e plasma, target
`conditioning time is reduced.
`
`3
`
`Figure 4. Spare-le unit located between an MDX and the vacuum chamber
`
`These accessories are installed between the MDX and the
`ch amber. All of the output power is run duough the Spare-le.
`There are three different modes in which the Spare-le can be
`operated: one passive mode, called ARC-OUT enhancement,
`and two active modes, active arc-handling and self-run.
`
`ARC-OUT ENHANCEMENT MODE
`Often, new sputtering targets contain many microscopic
`burrs, souvenirs of the machining and manufacturing process.
`During target conditioning, these burrs can act as electron field
`emission points that produce target arcs. If enough energy is
`delivered into d1e arc, the burrs will be burned away (melted)
`during the target-conditioning process.
`
`Iron ically, th e active modes of Spare-le and Spare are so
`effective in reducing d1e energy delivered during target arcing
`that conditioning such a target can take an inordinately long
`time. For this reason, a passive circuit similar to the enhanced
`version of ARC-OUT has been included in Spare-le and Spare.
`This ARC-OUT enhancement mode will deliver sufficient
`
`
`
`Case 6:20-cv-00636-ADA Document 78 Filed 03/10/21 Page 5 of 9
`
`HOW ADVANCED ENERGY, MDX™ PRODUCTS MANAGE ARCS
`
`Since this circuit has been further improved from the
`optional enhanced version available intemally in the MDX
`series, it can be thought of as an "improved enhanced" version
`of ARC-OUT This version of ARC-OUT, in Spare-le, can
`extinguish arcs with even wider latitude (Figure 5).
`
`ACTIVE ARC-HANDLING MODE
`r
`s
`pare- e nggere
`d
`
`oV
`
`~-
`/
`
`-6ooV
`
`j
`~
`
`I"
`
`v
`
`-
`
`ent_j
`Arc ev
`
`Time (2 µS/div)
`
`o A
`
`-20 A
`
`~ -....
`
`' I'
`
`-......
`
`-i-,...
`
`Arc event -
`
`Time (2 µS/div)
`
`Figure 6. Spare-le, in active arc-handling mode, reacts quickly to stop the
`formation of chamber arcs.
`
`The active arc-handling mode is designed to respond to
`chamber conditions that signal the beginning of an arc. Before
`an arc forms, the chamber voltage drops rapidly. The active
`circuit of Spare-le detects th is condition and activates an
`electronic switch. This switch does two important things. 1)
`It diverts the MDX current away from the chamber (and the
`potential arc), and 2) It acts to temporarily reverse the voltage
`on the target, drawing electrons from the load and killing the
`arc in the prenatal stage. This circuit function is extremely
`fast-
`the reaction time is l µs, and the total interruption of the
`process is only about 10 µs. In this mode, Spare-le can respond
`to up to 2000 arcs per second. This fast response can reduce the
`amount of energy dissipated in an arc (or potential arc) to one
`one-htmdredth of the energy dissipated in the active mode of
`
`4
`
`ARC-OUT (Figure 6), and about one one-thousandth of the
`eneq,,,y stored in the power supply's output circuits.
`
`SELF-RUN MODE
`The second active mode of Spare-le, the self-run mode, can
`be thought of as an "arc-prevention" mode. The self-run mode
`is especially valuable in reactive de sputtering processes that
`yield electrically insulative films. In d1is process, insulative
`layers can build up on conductive targets. These insulative areas
`cannot be sputtered away because the arriving ions eventually
`charge the surface to a positive potential, repelling further ions.
`The charged surface cannot be discharged because the insulator
`prevents electrons from d1e power supply from reaching d1e ions
`and neutralizing them. The resulting positive voltage on the
`front surface of the insulative layer creates a large voltage
`difference across the insulative layer because the back side of
`the layer is in direct contact wid1 the high negative voltage of
`the target. If this voltage difference between the front and back
`sides of the insulative layer exceeds d1e dielectric strength of the
`layer, a voltage breakdown will result; this breakdown can
`frequently initiate an arc.
`
`oV
`
`,.,.
`
`-6oo V
`
`J ,
`
`Spare
`-le _ /
`Self-activated
`
`r
`
`V
`
`-
`
`Time (2 µS/div)
`
`Figure 7. Spare-le, in self-run mode, reverses the chamber voltage 2000
`times per second to prevent arc-forming high voltage buildup.
`
`In the self-run mode, the electronic switch that reverses d1e
`target voltage is activated automatically (i.e., even in the
`absence of an arc), at a rate of 2000 times per second (Figure 7).
`This reversal of the voltage on the target will attract electrons
`from the plasma to the front surface of the insulative layer on
`the target. The arriving electrons neutralize the ions, restoring
`them to neutral gas atoms. This "discharges" d1e insulative
`layer, reducing the voltage difference between the front and
`back sides, which greatly reduces the probability of voltage
`breakdown and arc occurrence. In addition to preventing charge
`buildup, discharge of the insulative surface lowers the surface
`potential to the negative power supply voltage, which attracts
`positive ions from the plasma during the normal negative
`voltage period. This will sputter away the insulative layer, or
`
`
`
`Case 6:20-cv-00636-ADA Document 78 Filed 03/10/21 Page 6 of 9
`
`HOW ADVANCED ENERGY, MDX™ PRODUCTS MANAGE ARCS
`
`keep it so thin that it does not create an arcing hazard. It is
`important to note that if an arc does begin to form, between
`discharging pulses of the self-run mode, Spare-le will respond to
`the falling voltage, as in the nonnal active arc-handling mode,
`to suppress the arc (Figure 8).
`
`MDX
`
`+
`
`MDX
`
`+
`
`Figure 8. lnsulative Si02 builds up on target surface. Spare-le momentarily
`reverses target voltage to discharge the insulative layer Si02.
`
`Sometimes, problems encountered during the cond itioning
`of new targets are related to arcing that results from
`contamination and oxides on the target surface, rather than
`from the microscopic burrs d iscussed earlier. The self-run mode
`can also be used to "clean" insulative contamination or oxide
`layers from the target prior to use in normal (nomeactive) de
`sputtering processes. The insulative film will be sputtered away
`by the mechanism outlined above.
`
`An added feature of Spare-le is the activation port. This
`BNC connector allows the user to observe the operation of
`Spare-le. Every time an arc is repressed in the active arc(cid:173)
`handling mode, or every time the target voltage is discharged
`in the self-run mode, a 5 V, 10 ms signal is produced at the
`activation port. This signal can be monitored with an
`oscilloscope or frequency counter to track Sparc-le's operation.
`
`APPUCATIONS
`The ARC-OUT circuit in the MDX and Spare-le will
`enhance any vacuum process in which arc energy is a problem
`(not all processes are sensitive to arc energy). The ARC.
`C HEC K circuit is essential for cathodic arc deposition processes.
`It also brings significant value to sputtering processes that use
`magnetron cathodes with anodes that are close to cathodes and
`
`are therefore prone to target flake shorts. This is especially true
`in applications where sputtering is conducted in either a "side"
`or "up" sputtering configuration, where gravity can exacerbate a
`target flake short problem.
`
`Spare-Le's most significant contribution to the vacuum
`processing industry comes in the area of reactive de sputtering of
`electrically conductive or semiconductive targets in reactive gas
`environments, particularly where the reaction between gas and
`target produces an electrically insulative material. This
`revolutionary product permits the low cost and high sputter
`rates of de to be used effectively for sputtering these troublesome
`films. It should be pointed out that even though Spare-le has
`been shown to be very effective in sputtering insulative films
`fom1ed reactively from conductive targets, Spare-le will not
`work to pem1it de to sputter thick, truly insulative targets. This
`is true because iliick targets charge up so rapidly that much
`higher frequencies than Spare-le can produce are required to
`maintain sputtering action. Generally, the ISM (industrial,
`scientific, and medical) frequency of 13.56 MHz is used for RF
`sputtering of electrically insulative targets. Advanced Energy
`Industries, Inc., has a complete 13.56 MHz product line suitable
`for this purpose.
`
`The ARC-OUT enhancement mode of Spare-le will
`improve voltage bias supply perfom1ai1ce in catl1odic arc and
`ion-plating deposition processes by reducing the energy
`dissipated in arcs. Likewise, Spare-le operating in the active arc(cid:173)
`handling mode will further reduce arc-related damage in these
`processes.
`
`O ur experience in using Spare-le, in all modes, in processes
`that incorporate RF bias on substrates being coated, is excellent.
`We have not detected any interaction between Spare-le ai1d the
`RF bias source, and ilie function of Spare-le is unaffected.
`
`This paper was written to clarify the numerous and
`complex arc-mai1aging schemes and designs incorporated in de
`products engineered and manufactured by Advanced Energy
`Industries, Inc. If you have any questions, or desire further
`infom1ation on a higher teclrnical level regarding ai1y of these
`designs or processes, please contact ilie technical support or
`technical education department of Advanced Energy Industries,
`Inc.
`
`5
`
`
`
`Case 6:20-cv-00636-ADA Document 78 Filed 03/10/21 Page 7 of 9
`
`HOW ADVANCED ENERGY, MDX™ PRODUCTS MANAGE ARCS
`
`6
`
`
`
`Case 6:20-cv-00636-ADA Document 78 Filed 03/10/21 Page 8 of 9
`
`HOW ADVANCED ENERGY, MDX™ PRODUCTS MANAGE ARCS
`
`7
`
`
`
`Case 6:20-cv-00636-ADA Document 78 Filed 03/10/21 Page 9 of 9
`
`HOW ADVANCED ENERGY, MDX™ PRODUCTS MANAGE ARCS
`
`1\ -C ADVANCED
`Lil ENERGY®
`
`Cl Advanced Ene~ lndustrio.. Inc.
`All riJ?hts rCSC:l'Vcd. PrinLcd in USA
`SL-WHITEl9-27Q.-OI IM 03/01
`
`Advanced Energy Industries, Inc.
`1625 Sharp Point Drive
`Fort Collins, Colorado 80525
`800.446.9167
`970.221.4670
`970.221.5583 (fax)
`support@aei.com
`www.advanced,energy.com
`
`California
`T: 408.263.8784
`F: 408.263.8992
`
`New Jersey
`T: 856.627.6100
`F: 856.627.6159
`
`United Kingdom
`T: 44.1869320022
`F: 44.1869325004
`
`Germany
`T: 49.711.779270
`F: 49.711.7778700
`
`Korea
`T: 82.31.705.2100
`F: 82.31.705.2766
`
`Japan
`T: 81.3.32351511
`F: 81.3.32353580
`
`Taiwan
`T: 886.2.82215599
`F: 886.2.82215050
`
`China
`T: 86.755.3867986
`F: 86. 755.3867984
`
`8
`
`