Solid State Matcher (SSM) - Generator Synchronization

Abstract

The present disclosure relates generally to power systems. Specifically, but not by way of limitation, the present disclosure relates to impedance matching networks. The present disclosure describes a system, method, and apparatus for a power system comprising a generator connected to a solid-state matching network and a synchronization module connected to the generator and the solid-state matching network, the synchronization module being configured to synchronize the opening and closing of switches in the solid-state matching network with the power delivered by the generator to the matching network.

Description

[Technical field]

[0001] (Claim of priority under 35 USC Section 119) This application for patent claims priority to Provisional Application No. 63 / 300,100, entitled “SOLID-STATE MATCH (SSM)-GENERATOR SYNCHRONIZATION,” filed on January 17, 2022, which is assigned to the assignee hereof and expressly incorporated herein by reference. FIELD OF THE DISCLOSURE

[0002] The present disclosure relates generally to power systems and, more particularly, but not by way of limitation, to impedance matching networks. [Background technology]

[0003] Description of Related Art In the context of plasma processing, manufacturers use plasma processing chambers that utilize power (e.g., radio frequency (RF) power) to generate a plasma. To achieve efficient power transfer between the generator and the plasma load, an impedance matching network ("matching network") is often used to match the load impedance to a desired input impedance, typically (but not always) 50 ohms. The plasma load impedance may vary depending on variables such as generator frequency, power, chamber pressure, gas composition, and plasma ignition. The matching network accounts for these variations in the load impedance by varying a reactive element (e.g., a variable capacitor) to maintain the desired input impedance.

[0004] RF matching networks have utilized variable vacuum capacitors for many years, but solid-state matchers (SSMs), which include discrete capacitors that are switched on and off to modify the value of the capacitor within the SSM, are now an alternative technology that is gaining popularity because SSMs can be switched more quickly, and faster switching can allow for faster matching, which allows for better process control.

[0005] As known in the art, PIN diodes may be used to switch reactive elements (e.g., capacitors and inductors) on and off from solid-state matchers. A PIN diode is an electrical diode device with an undoped or lightly doped intrinsic (I) semiconductor region sandwiched between a heavily doped p-type semiconductor region (P) and a heavily doped n-type semiconductor region (N), hence the name "PIN diode." In general, PIN diodes follow traditional diode behavior at low frequency input signals, but at higher input signal frequencies, they behave as a resistor in the forward bias or on state and as a small capacitor in the reverse bias or off state.

[0006] High speed PIN diode drivers with energy recovery beneficially allow PIN diodes to be switched at high repetition rates, such as 10 kHz. However, during the short periods (approximately 2 μs) during which the PIN diode transitions between the on and off states, dissipation can be high due to high applied RF voltages and currents. High dissipation can reduce the overall reliability of the system. Thus, there is a need for a refined power system that reduces these short periods of high dissipation.

[0007] A description provided in the Description of Related Art section should not be considered prior art merely because it is mentioned in or associated with this section. The Description of Related Art section may include information that describes one or more aspects of the present technology. Summary of the Invention [Means for solving the problem]

[0008] (Summary of the Disclosure) The following presents a simplified summary related to one or more aspects and / or embodiments disclosed herein. As such, the following summary should not be considered an extensive overview related to all envisioned aspects and / or embodiments, nor should the following summary be considered to identify key or critical elements related to all envisioned aspects and / or embodiments or to delimit the scope associated with any particular aspect and / or embodiment. Thus, the following summary has the sole purpose of presenting certain concepts related to one or more aspects and / or embodiments related to the mechanisms disclosed herein in a simplified form prior to the detailed description presented below.

[0009] Aspects of the present disclosure relate generally to systems, methods, and apparatus for solid-state matcher circuits, and more specifically, for synchronizing power delivery from a generator with the on-to-off and off-to-on transitions of switches (e.g., PIN diodes) in a solid-state matcher to which the generator is connected.

[0010] Due to the high dissipation in the transition, virtually none of the power provided by the generator reaches the load. By reducing the RF power (or even cutting off the RF power entirely) for the short period of time while the switch (e.g., a PIN diode) transitions between states, the dissipation in the switch is substantially reduced and has little effect on the load because the load will not receive any of the power the generator is delivering at any rate due to the high dissipation in the switch.

[0011] Reducing the periods of peak power dissipation allows sustained switching at high repetition rates. Without this power reduction, the average dissipation in the switch becomes the limiting factor to how much the repetition rate can be sustained.

[0012] In some aspects, the techniques described herein include a solid-state matcher (SSM) network having a load side and a source side and one or more switches therebetween; a generator connected to the source side of the SSM network; a plurality of control sources for controlling power delivered by the generator to the SSM network, the plurality of control sources including at least a first control source configured to output a first control signal and a second control source configured to output a second control signal; and a synchronization module connected to the generator and the SSM network, the synchronization module obtaining timing information from the SSM network, the timing information being transmitted to one or more of the SSM networks. and a synchronization module configured to synchronize power delivered by the generator to the SSM network based, at least in part, on the timing information, the synchronization including information regarding a period when a switch in the SSM network or more changes state from an open state to a closed state or vice versa, the synchronization including selecting one of a first controlled source and a second controlled source to connect to the generator, and one of suspending, reducing, resuming, or increasing power delivered by the generator to the SSM network at or around the period when one or more switches in the SSM network change state.

[0013] In some aspects, the techniques described herein relate to a power delivery system, where a generator includes a first controlled source and a synchronization module includes a second controlled source for amplitude control.

[0014] In some aspects, the techniques described herein relate to a power delivery system where, when a second controlled source is connected to the generator, the synchronization module is configured to suspend power delivered by the generator to the SSM network for a period surrounding when one or more switches of the SSM network change state.

[0015] In some aspects, the techniques described herein relate to a power delivery system where, when a second controlled source is connected to the generator, the synchronization module is configured to reduce the power delivered by the generator to the SSM network for a period surrounding when one or more switches of the SSM network change state.

[0016] In some aspects, the techniques described herein relate to a power delivery system, wherein the synchronization module is further configured to estimate a temperature of at least one device in the SSM network, compare the temperature to a threshold, and, when the temperature exceeds the threshold, transmit an indication to the generator to suspend power delivery to the SSM matching network for at least one period at or around the time when one or more switches of the SSM network change state.

[0017] In some aspects, the techniques described herein relate to a power delivery system, wherein the synchronization module is further configured, at least in part, based on detecting that the temperature falls below a threshold, to transmit another indication to the generator to resume power delivery to the SSM network at or for at least one period of time around when one or more switches of the SSM network change state.

[0018] In some aspects, the techniques described herein relate to a power delivery system, wherein the synchronization module is further configured to estimate a temperature of at least one device in the SSM network, compare the temperature to a threshold, and, when the temperature exceeds the threshold, transmit an indication to the generator to reduce power delivery to the SSM matching network for at least one period at or around when one or more switches of the SSM network change state.

[0019] In some aspects, the techniques described herein relate to a power delivery system, wherein the synchronization module is further configured, at least in part, based on detecting that the temperature is below a threshold, to transmit another indication to the generator to increase power delivery to the SSM network for at least one period at or around when one or more switches of the SSM network change state.

[0020] In some aspects, the techniques described herein relate to a power delivery system further including a plasma load connected to the SSM network.

[0021] In some aspects, the techniques described herein relate to a power delivery system, where a generator includes a first control source and a synchronization module includes a second control source for amplitude control and a third control source for timing control, where the third control source adjusts timing for connecting one of the first control source and the second control source to a power amplifier of the generator and disconnecting another of the first control source and the second control source from the power amplifier.

[0022] In some aspects, the techniques described herein relate to a synchronization module including one or more hardware processors configured to: identify, with machine-readable instructions, a first control source, the first control source outputting at least one first control signal; identify a second control source, the second control source outputting at least one second control signal; obtain timing information from a solid-state matching network, the solid-state matching network including one or more switches, the timing information including information regarding time periods when the one or more switches change state; and determine, at least in part, based on the timing information, two or more of a first period during which the first control source is active, a second period during which the second control source is active, and a time for switching from the first control source to the second control source or vice versa.

[0023] In some aspects, the techniques described herein relate to a synchronization module, wherein the one or more hardware processors are further configured, via the machine-readable instructions, to receive feedback information relating to data measured during one or more of the first time period and the second time period, and to adjust one or more of the at least one first control signal and the at least one second control signal based, at least in part, on the feedback information.

[0024] In some aspects, the techniques described herein relate to a synchronization module that is electronically, logically, or communicatively coupled to a generator and a solid-state matching network, the generator including a power amplifier configured to receive at least one first control signal from a first control source and at least one second control signal from a second control source, and at least one switch.

[0025] In some aspects, the techniques described herein relate to a synchronization module, wherein the one or more hardware processors are further configured to control, with machine-readable instructions, at least one switch in the generator, where controlling the at least one switch in the generator includes coupling the power amplifier to a first control source for a first time period, transitioning control of the power amplifier from the first control source to a second control source, and coupling the power amplifier to the second control source for a second time period.

[0026] In some aspects, the techniques described herein relate to a synchronization module, wherein the one or more hardware processors are further configured with machine-readable instructions to transmit an indication to the power amplifier to one of suspend, reduce, or increase the power output for one or more time periods when one or more switches of the solid-state matching network change state, the indication being received via one of the first control signal and the second control signal.

[0027] In some aspects, the techniques described herein relate to a synchronization module, wherein the one or more hardware processors are further configured by the machine-readable instructions to receive feedback information related to a power level measured for at least one duration when power output from the power amplifier is paused, reduced, or increased, and to adjust one or more of the at least one first control signal, the at least one second control signal, the first period, and the second period based, at least in part, on the feedback information.

[0028] In some aspects, the techniques described herein relate to a non-transitory tangible computer-readable storage medium encoded with processor-readable instructions for performing a method for operating a power delivery system, the method including: identifying a first control source, the first control source outputting at least one first control signal; identifying a second control source, the second control source outputting at least one second control signal; obtaining timing information from a solid-state matching network, the solid-state matching network including one or more switches, the timing information including information regarding a period when the one or more switches change state from an open state to a closed state or vice versa; and determining, at least in part based on the timing information, two or more of a first period during which the first control source is active, a second period during which the second control source is active, and a time for switching from the first control source to the second control source or vice versa.

[0029] In some aspects, the techniques described herein relate to a non-transitory tangible computer-readable storage medium, wherein a solid-state matching network is connected to a generator, and the method further includes synchronizing power delivery by the generator to the solid-state matching network based at least in part on the timing information, the synchronizing including selecting one of a first controlled source and a second controlled source to connect to the generator, and one of suspending, reducing, resuming, or increasing power delivered by the generator to the solid-state matching network at or around a period when one or more switches of the solid-state matching network change state.

[0030] In some aspects, the techniques described herein relate to a non-transitory tangible computer-readable storage medium, where the method further includes receiving feedback information relating to data measured during one or more of the first time period and the second time period, and adjusting one or more of the at least one first control signal and the at least one second control signal based, at least in part, on the feedback information.

[0031] In some aspects, the techniques described herein relate to a non-transitory tangible computer readable storage medium, the method further including connecting a solid-state matching network to a plasma load.

[0032] These and other features and characteristics of the present technology, as well as the method of operation and function of the associated elements of construction, and combination with economy of parts and manufacture, will become more apparent upon consideration of the following description and appended claims, with reference to the accompanying drawings, all of which form a part of this specification and in which like reference numerals designate corresponding parts in the various views. It is to be expressly understood, however, that the drawings are for purposes of illustration and description only and are not intended as a definition of the limits of the invention. As used in this specification and claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. [Brief description of the drawings]

[0033] Various objects and advantages of the present disclosure as well as a more complete understanding will become apparent and will be more readily understood by reference to the following detailed description and appended claims, when considered in conjunction with the accompanying drawings.

[0034] [Figure 1] FIG. 1 is a block diagram illustrating a power system in accordance with various aspects of the disclosure.

[0035] [Diagram 2]FIG. 2 is a block diagram illustrating a power system in accordance with various aspects of the disclosure.

[0036] [Figure 3A] FIG. 3A is a block diagram illustrating a switched variable reactance element in accordance with various aspects of the disclosure.

[0037] [Figure 3B] FIG. 3B is a block diagram illustrating a switched variable reactance element in accordance with various aspects of the disclosure.

[0038] [Figure 4] FIG. 4 is a block diagram illustrating a PIN diode switch in accordance with various aspects of the disclosure.

[0039] [Figure 5A] FIG. 5A illustrates a schematic diagram of an equivalent circuit for a PIN diode in an on-state in accordance with various aspects of the present disclosure.

[0040] [Figure 5B] FIG. 5B illustrates a schematic diagram of an equivalent circuit for a PIN diode in an off state in accordance with various aspects of the present disclosure.

[0041] [Figure 6] FIG. 6 illustrates waveforms in a power system in accordance with various aspects of the present disclosure.

[0042] [Figure 7] FIG. 7 illustrates waveforms in a power system in accordance with various aspects of the disclosure.

[0043] [Figure 8] FIG. 8 illustrates waveforms in a power system in accordance with various aspects of the disclosure.

[0044] [Figure 9] FIG. 9 illustrates waveforms in a power system in accordance with various aspects of the disclosure.

[0045] [Figure 10] FIG. 10 is a block diagram illustrating a power system in accordance with various aspects of the disclosure.

[0046] [Figure 11] FIG. 11 illustrates a thermal model in accordance with various aspects of the present disclosure.

[0047] [Figure 12A] FIG. 12A illustrates dissipation and temperature waveforms for a solid-state matcher in accordance with various aspects of the present disclosure.

[0048] [Figure 12B] FIG. 12B illustrates dissipation and temperature waveforms for a solid-state matcher in accordance with various aspects of the present disclosure.

[0049] [Figure 12C] FIG. 12C illustrates dissipation and temperature waveforms for a solid-state matcher in accordance with various aspects of the present disclosure.

[0050] [Figure 13A] FIG. 13A illustrates dissipation and temperature waveforms for a solid-state matcher in accordance with various aspects of the present disclosure.

[0051] [Figure 13B] FIG. 13B illustrates dissipation and temperature waveforms for a solid-state matcher in accordance with various aspects of the present disclosure.

[0052] [Figure 13C] FIG. 13C illustrates dissipation and temperature waveforms for a solid-state matcher in accordance with various aspects of the present disclosure.

[0053] [Figure 14] FIG. 14 illustrates an example of a method for operating a power system in accordance with various aspects of the disclosure.

[0054] [Figure 15] FIG. 15 illustrates an example of a method for operating a power system according to various aspects of the disclosure.

[0055] [Figure 16] FIG. 16 illustrates an example of a method for operating a power system according to various aspects of the disclosure.

[0056] [Figure 17] FIG. 17 illustrates an example of a method for operating a power system according to various aspects of the disclosure.

[0057] [Figure 18] FIG. 18 illustrates a block diagram of a computer system that can be used to implement one or more aspects of the disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0058] (Detailed Description) Prior to describing the embodiments in detail, it is convenient to define certain terms as used in this disclosure.

[0059] The word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.

[0060] Preliminary note: the flow charts and block diagrams in the following figures illustrate the functionality and operation of possible implementations of a power system comprising a generator connected to a solid-state matching network, according to various embodiments of the present disclosure. It should be noted that in some alternative implementations, the functions described in each block may occur outside the order described in the figures. For example, two blocks shown in succession may in fact be performed substantially in parallel, or the blocks may sometimes be performed in the reverse order, depending on the functionality involved. For example, an operation of reducing the power delivered by the generator for a period of time surrounding the opening and closing of a switch in the solid-state impedance matching network when the temperature exceeds a threshold value can be replaced by, or performed in parallel with, increasing the power delivered by the generator for a period of time surrounding the opening and closing of a switch in the solid-state impedance matching network when the temperature falls below the threshold value and the generator power is now reduced.

[0061] Delivered power is often lost when a switch in a solid-state matcher (SSM) changes state. In a power delivery system that includes a generator, an SSM, and a load, sustaining normal power delivery for short periods when the switch in the SSM changes state may lead to unnecessary heating in the SSM, which may limit the maximum rate at which the SSM may change state without suffering damage. In addition, sustaining normal power delivery may be wasteful (i.e., power is wasted rather than delivered to the load) because a significant portion of the delivered power may not reach the load during these short periods when the switch in the SSM changes state. Because the amount of power lost in the switch may be difficult to estimate, sustaining normal power delivery may result in an uncertain amount of energy being delivered to the load, which may be detrimental to processes (e.g., semiconductor processing in a plasma chamber) where precise power delivery may be required. Broadly, the present disclosure describes systems, methods, apparatus, and / or storage media for reducing, if not turning off, power delivery from a generator around the time when the PIN diodes for switching components of an SSM change state, which not only helps to reduce the power dissipated in the PIN diode switches, but also helps to increase the rate at which the SSM can change state.

[0062] FIG. 1 illustrates an example of a power system 100 adapted for synchronous control in accordance with various aspects of the disclosure. The power system 100 includes a generator 102, a solid-state matcher (SSM) 104, a load 106, and a synchronization module 112. The synchronization module 112 may synchronize the power delivery of the generator 102 with the operation of the SSM 104. In some examples, the load 106 may be a plasma load and the generator 102 may be a radio frequency (RF) generator. In some cases, the synchronization module may be implemented within the generator 102 or, alternatively, within the SSM 104. In other cases, the synchronization module 112 may be implemented as a separate unit.

[0063] The generator 102 applies RF power through a transmission line 108 (e.g., a coaxial cable) to a matching network 104 and then through an electrical connection 110 onto a load 106 (e.g., a nonlinear load such as a plasma load). The SSM 104 (also referred to as the matching network 104) is connected to the input impedance Z in is the target input impedance Z t (e.g., 50 Ω) (i.e., within the threshold range, e.g. [ka] And, [ka] is Z t The matching network varies its internal electrical elements (e.g., a variable capacitor) so that the impedance of the matching network is a complex conjugate of the impedance of the matching network. Matching networks typically contain reactive elements, meaning elements that store energy in electrical and magnetic fields, as opposed to resistive elements, which dissipate power. The most common reactive elements are capacitors, inductors, and coupled inductors, but others such as distributed circuits are also used.

[0064] FIG. 2 illustrates a schematic diagram of a power system 200 adapted for synchronous control in accordance with various aspects of the disclosure. The power system 200 implements at least one or more aspects of other power systems described herein, including the power system 100 described in connection with FIG. 1. The power system 200 may include a generator 202, a solid-state matching network 204, a load 206, and a synchronization module 212. Some solid-state matching networks 204 include two or more variable reactance elements, such as the variable capacitors 230 and 232 shown in FIG. 2. In some embodiments, one or more of the variable capacitors 230 and 232 may include multiple switched capacitors. For example, one or more of the variable capacitors 230, 232 may include multiple split and full value capacitors, where individual ones of the variable capacitors 230 and 232 may be switched on and off. By switching a combination of split and full value capacitors into a variable capacitor, a capacitance between a minimum and a maximum capacitance can be achieved, thereby allowing the capacitance of the variable capacitor to be varied.

[0065] Although two variable capacitors 230 and 232 are shown in FIG. 2, this is not intended to be limiting. For example, in some embodiments, a single variable capacitor or three or more variable capacitors may be utilized within the power system 200. One or more inductors may also be arranged before the variable capacitors (e.g., inductor 260 positioned toward the generator or source side) or between them (e.g., inductor 262), with the illustrated configuration being only one of many implementations. The variable reactance section 222, which includes the variable capacitors 230, 232, can be arranged with the fixed reactance sections 220 and 224. In this example, the fixed reactance section 220 comprises the inductor 220, while the fixed reactance section 224 comprises two inductors 264, 266 and a capacitor 269 arranged in a T-configuration. It should be noted that other variations of the fixed reactive sections 220, 224 are also contemplated, for example, using a different number of inductors and / or capacitors, different configurations (e.g., a Pi configuration instead of a T configuration), or combinations thereof. Together, the fixed and variable reactance sections 220, 222, and 224 comprise the matching network 204.

[0066] In some embodiments, the solid-state matcher (SSM) 204 also includes a first control source (e.g., controller 214) for controlling the variable reactance elements 230 and 232, although in some embodiments the controller 214 can be remote from the SSM (e.g., part of the synchronization module 212). The controller 214 may be in communication with a synchronization module 212, which synchronizes the operation of the SSM 204 with the power delivery of the generator 202. In some examples, the synchronization module 212 may include one or more additional control sources (e.g., a second control source, shown in FIG. 10 as an amplitude control module 1030, a third control source, shown in FIG. 10 as a timing control module 1032).

[0067] 3A illustrates a block diagram 300-a of a switched variable reactance element (e.g., switched variable capacitors 230 and / or 232 of FIG. 2) that may be used in designing an impedance matching network (e.g., solid-state matcher 204 of FIG. 2) according to various aspects of the disclosure. The variable reactance element 300-a comprises a first terminal 330, a second terminal 331, a number of reactances (e.g., reactance 311, reactance 312, reactance 313, reactance 314), and a number of switches (e.g., switch 301, switch 302, switch 303). In the variable reactance element 300-a, reactances Y1, Y2, ...Y N are switches S1, S2, ..., S N 3. Closing a switch in series with a reactance (e.g., switch S2 in series with reactance Y2) adds the susceptance of that reactance to the total susceptance of the variable reactance element (e.g., variable reactance element 300-a). Variable reactance element 300-a can also contain one or more fixed reactances 314 that are not arranged in series with a switch.

[0068] 3B illustrates a block diagram 300-b of a switched variable reactance element (e.g., switched variable capacitor 230 and / or 232 of FIG. 2) that may be used in designing an impedance matching network (e.g., solid-state matcher 204 of FIG. 2) according to various aspects of the disclosure. The variable reactance element shown in FIG. 3B comprises a first terminal 370, a second terminal 371, a number of reactances (e.g., reactances 351-353, reactance 356), and a number of switches (e.g., switches 341-343). In the variable reactance element 300-b, reactances X1, X2, ...X N are switches S1, S2, …, S N where reactances X1, X2, …, X N are switches S1, S2, ..., S N3. Opening a switch that shunts a reactance (e.g., switch S1, shunting reactance X1) adds the reactance of that reactance to the total reactance of the variable reactance element 300-b. The variable reactance element may also contain one or more fixed reactances 356 that are not shunted by a switch.

[0069] A PIN diode is an electrical device that has an undoped or lightly doped intrinsic (I) semiconductor region sandwiched between heavily doped regions and has a variety of uses, for example, as a switching device in impedance matching networks, particularly radio frequency (RF) matching networks. The "PIN" designation comes from the diode's three-part "sandwich" structure, i.e., a lightly doped intrinsic region (I) positioned between a heavily doped p-type semiconductor (P) and a heavily doped n-type semiconductor (N).

[0070] Generally, PIN diodes follow conventional diode behavior for low frequency input signals, but for higher frequency input signals, they behave as resistors in the forward bias or on state and as capacitors in the reverse bias or off state. Thus, PIN diodes are often utilized in radio frequency (RF) applications, for example, in attenuators and high speed switches where high isolation and low loss are required. In some situations, PIN diodes can be turned on with a DC current that is a small fraction of the RF current being switched, and turned off by reverse biasing the PIN diode. PIN diodes are attractive switches because they combine low on-state resistance with very low off-state losses. In some cases, a PIN diode driver circuit can be used to turn PIN diodes on and off by conducting DC current through the PIN diode and applying a reverse bias voltage across the PIN diode, respectively.

[0071] In one implementation, PIN diodes are used in an impedance matching network configured to match the varying load impedance of a plasma load to a target impedance (e.g., 50 ohms) into which a high-power RF generator can deliver power. In such an implementation, the PIN diodes serve to quickly modify the nature of the matching network by connecting or disconnecting reactive components, such as capacitors and / or inductors, of the impedance matching network, switching reactive elements on and off of the network.

[0072] 4 illustrates a block diagram 400 of a PIN diode switch in accordance with various aspects of the disclosure. In some embodiments, the PIN diode switch 400 includes switches S1, S2, ..., S3 of the variable reactance element 300-a in FIG. N and / or the switches S1, S2, ..., S of the variable reactance element 300-b in FIG. N As described above, one or more of the variable reactance elements 300-a and 300-b may be used in the design of an impedance matching network (e.g., solid-state matcher 204 of FIG. 2).

[0073] Optional capacitor 430 may be desirable if a DC current path exists through the network connected between switch terminals 440 and 442. In many applications, a DC path may not exist (e.g., when the switch is in series with the capacitor, as is often the case with switched variable capacitor elements), and optional capacitor 430 may not be required. To turn on the switch (i.e., create a small impedance between terminals 440 and 442), DC current is conducted through PIN diode 402. This may be accomplished by closing switch 418 (switch 420 is in an open state), which is coupled in series with low voltage forward bias current source 410. Conducting a small (e.g., 700 mA) current through PIN diode 402 causes PIN diode 402 to act like a small (e.g., 0.15 Ω) resistor to RF current, thereby presenting a low RF impedance between switch terminals 440 and 442. To turn the switch off (i.e., create a large impedance between terminals 440 and 442), a reverse bias voltage is applied across the PIN diode 402. This may be accomplished by closing switch 420 (switch 418 is in an open state), which is coupled in series with the high voltage reverse bias voltage source 414. The reverse bias PIN diode 402 causes the PIN diode 402 to act as a small (e.g., 4 pF) capacitor to the RF current. The magnitude of the applied reverse bias voltage may be greater than the maximum RF voltage that may be applied between terminals 440 and 442. A typical reverse bias voltage may be 1,500V.

[0074] An equivalent forward bias ("on") circuit 500-a for a PIN diode, such as PIN diode 402, that may be used as a switch in the design of a variable reactance element is illustrated in FIG. 5A. Typical values ​​for the resistors in FIG. 5A are 0.15 Ω and typical values ​​for the inductors in FIG. 5A are 1 nH, although other resistance and inductance values ​​are contemplated in different embodiments. PIN diodes are often used as switches in variable reactance elements because in the on state they act like a small (e.g., 0.15 Ω) resistor for RF currents and in the off state as a small capacitor (e.g., 4 pF).

[0075] An equivalent reverse bias ("off") circuit 500-b for a PIN diode such as PIN diode 402 is illustrated in Figure 5B. The equivalent circuit includes an inductor in series with a parallel combination of a resistor and a capacitor. A typical value for the inductance in Figure 5B is 1 nH, a typical value for the capacitor is 4 pF, and a typical value for the resistor is 1.6 MΩ.

[0076] FIG. 6 illustrates an example waveform 600 in a conventional power delivery system, where power delivery is not interrupted during switching. The top plot 602 shows the normalized available power from a generator (e.g., generator 102 of FIG. 1) as a function of time. In a typical application, a normalized power of 1 may correspond to, for example, 3 kW. Plot 602 shows that at 15 microseconds, the normalized available power of the generator decreases, changing from 1 to 0.81. The two normalized powers shown (1 and 0.81) may represent two different states, where the generator may have different power set points and output different frequencies in the two different states. In some situations, a conventional power delivery system may alternate between the two different states, for example, at a 10 kHz rate. The available power, also referred to as forward power and actual delivered power (i.e., power that can be converted to an equivalent amount of heat), is the available power minus the reflected power. Generators typically operate in either forward or delivered power modes, but because the generator control system is typically not fast enough to respond to changes in load impedance, which occur on the scale of microseconds, a typical generator may only be able to keep the available power approximately constant, even when attempting to keep the delivered power constant.

[0077] The second plot 604 from the top shows the voltage across a switch of a variable reactance element in a matching network, the matching network being connected between a generator and a load. As shown in plot 604, between 0 and 15 microseconds and again between 65 and 100 microseconds, the voltage across the switch is low. In addition, as shown in plot 606, the current through the switch is high halfway between 0-15 microseconds and 65-100 microseconds, meaning the switch is closed or on. Between 15 and 65 microseconds, the voltage across the switch is high (as shown in plot 604) and the current through the switch is low (as shown in plot 606), meaning the switch is open or off. Both the voltage (e.g., switch voltage in plot 604) and current (e.g., switch current in plot 606) are normalized. For example, a value of 1 in voltage plot 604 may correspond to a voltage of approximately 1,000 V, while a value of 1 in current plot 606 may correspond to a current of approximately 15 A. The largest contributions to both the voltage of plot 604 and the current of plot 606 are the RF voltage and current (i.e., as opposed to DC voltage and current). A typical frequency for the RF voltage and current may be 13.56 MHz.

[0078] The second-lowest plot 608 shows the fraction of available power from a generator (e.g., generator 102 of FIG. 1 ) that is delivered to a load (e.g., load 106 of FIG. 1 ), referred to herein as load power. As illustrated in plot 608, there are two dips 620 and 622 in load power at about 15 microseconds and about 65 microseconds, respectively. The dips 620, 622 may be due in part to a shift in load impedance that increases reflected power and causes the delivered power to drop, but some of this power may also be due to the switches (e.g., switches S1, S2, ..., S) of the variable reactance element (e.g., variable reactance element 300-a of FIG. 3A ). N) in the power delivery system (e.g., power delivery system 200 of FIG. 2). In some cases, the variable reactance element may be used as a variable reactance element (e.g., variable capacitors 230 and 232 of solid-state matcher 204 of FIG. 2) in a solid-state matcher (e.g., matcher 204 of FIG. 2) in the power delivery system (e.g., power delivery system 200 of FIG. 2).

[0079] Plots 608 and 610 of Figure 6 show that when a switch in a solid-state matcher (e.g., SSM 204 of Figure 2) is switched, the power delivery to the load is reduced, as depicted by dips 620 and 622, and power is dissipated in the switch of the variable reactance element of the solid-state matcher (e.g., matcher 204 of Figure 2), as depicted in plot 610 by the increase in power dissipated in switch 624. The bottom plot 610 depicts switch power (i.e., the fraction of available generator power that is dissipated in the switch) versus time. As can be seen, power that could be recovered by the system is instead lost as heat in the switch during the two illustrated switching events.

[0080] Using implementation of the synchronization scheme disclosed herein, the plot in Fig. 7 can be achieved. Fig. 7 illustrates an example waveform 700 within a power delivery system, such as power delivery systems 100 and / or 200 in Figs. 1 and / or 2, respectively. In some examples, the power delivery system includes a generator that is turned off or provides reduced power during and around the switching event. In other words, the example waveform 700 corresponds to a power delivery system in which power delivery is synchronized with switching, according to aspects of the present disclosure.

[0081] As shown in the top plot 702 of Figure 7, rather than delivering power during the time that a switch in a solid-state matcher (e.g., matcher 204 of Figure 2) changes state (i.e., switches from on to off or off to on), power is briefly interrupted for a period around the time that a switch in the SSM changes state, as depicted by 730 and 732 in plot 702. Additionally, as shown by 720 and 722 in plot 708, power delivery by the generator (e.g., generator 202 of Figure 2), and therefore to the load (e.g., load 206 of Figure 2), is interrupted around the time that the switch changes state. However, in terms of average and total power delivered, the reduction in power is relatively small. Moreover, power delivery to the load is only slightly reduced because in the conventional system there is already an interruption in the power delivered to the load (compare 720 and 722 in plot 708 of FIG. 7 with the conventional interruptions at 620 and 622 in plot 608 in FIG. 6), and on the positive side, significantly less power is dissipated in the switch as shown by 724 (compare 624 in plot 610 in FIG. 6). With the power delivery system associated with waveform 700, the power is interrupted for a slightly longer period of time, but is better controlled, which can be an advantage in many applications. Specifically, power is better controlled because periods of uncertain power delivery 620 and 622 (e.g., uncertainty regarding the amount of available generator power delivered to the load and / or uncertainty regarding the duration of the low power periods) are replaced by periods of certain power delivery 720 and 722 (e.g., zero power is delivered to the load for periods of known duration), thereby allowing a more accurate determination of the energy delivered to the load (e.g., over a period of 0 to 100 microseconds as shown in FIG. 7).

[0082] In some embodiments, the synchronization scheme illustrated in FIG. 7 may be used for selected periods of time, but not during other times. For example, if PIN diode temperature and / or power dissipation are monitored and used in a feedback loop, the synchronization illustrated by FIG. 7 may be utilized when temperature and / or power dissipation exceed a threshold. Once temperature and / or power dissipation return to acceptable levels, synchronization may be turned off, for example, by returning to a scheme that results in power delivery as illustrated in FIG. 6. In other words, the present disclosure may include switching between power delivery schemes as illustrated in FIGS. 6 and 7 in response to a feedback loop, such as one based on PIN diode switch temperature and / or power dissipation. This alternation between full power (e.g., FIG. 6) and reduced power via synchronization (e.g., FIG. 7) may be based on feedback from switch element seam temperature, heat sink temperature, and / or ambient temperature, to name a few non-limiting examples.

[0083] FIG. 8 illustrates example waveforms 800 in a power delivery system, such as the power delivery system 100 of FIG. 1, operated in accordance with various aspects of the disclosure. As shown in the top plot 802 of FIG. 8, rather than delivering full power during the time that a switch in a solid-state matcher (e.g., matcher 204 of FIG. 2) changes state (i.e., switching from on to off or off to on), the power is reduced for a short period of time around the time that the switch in the SSM changes state, as depicted by 830 and 832 in plot 802. Additionally, as shown by 820 and 822 in plot 808, the power delivery by the generator (e.g., generator 202 of FIG. 2), and therefore to the load (e.g., load 206 of FIG. 2), is reduced for a period of time around the time that the switch changes state. However, in terms of average and total power delivered, the reduction in power is relatively small. Moreover, power delivery to the load is only slightly reduced because in the conventional system there is already an interruption in the power delivered to the load (compare 820 and 822 in plot 808 of FIG. 8 with the conventional interruptions at 620 and 622 in plot 608 in FIG. 6), and on the positive side, significantly less power is dissipated in the switch as shown by 824 (compare 624 in plot 610 in FIG. 6). With the power delivery system associated with waveform 800, the power is interrupted for a slightly longer period of time, but is better controlled, which can be an advantage in many applications. Power is better controlled because periods of uncertain power delivery 620 and 622 (e.g., uncertainty about the amount of available generator power delivered to the load and uncertainty about the duration of the low power periods) are replaced by periods where power delivery 820 and 822 is more certain (e.g., low power is delivered to the load for periods of known duration), thereby allowing a more accurate determination of the energy delivered to the load (e.g., over a period of 0 to 100 microseconds as shown in FIG. 8).

[0084] In some embodiments, the synchronization scheme illustrated in FIG. 8 may be used for selected periods of time, but not during other times. For example, if PIN diode temperature and / or power dissipation are monitored and used in a feedback loop, the synchronization illustrated by FIG. 8 may be utilized when temperature and / or power dissipation exceed a threshold. Once temperature and / or power dissipation return to acceptable levels, synchronization may be turned off, for example, by returning to a scheme that results in power delivery as illustrated in FIG. 6. Alternatively, the scheme represented by FIGS. 7 and 8 may be implemented in the same manner as FIG. 6. For example, if the reduced power of FIG. 7 is used initially when a temperature threshold is exceeded, power may be delivered according to FIG. 8 before returning to FIG. 6 (FIG. 8 delivers more power than FIG. 7, but less power than FIG. 6). In other words, the present disclosure may include switching between power delivery schemes as illustrated in FIGS. 6 and 8 (or 6, 7, and 8) in response to a feedback loop, such as one based on PIN diode switch temperature and / or power dissipation. This alternation between full power (e.g., FIG. 6) and reduced power via synchronization (e.g., FIG. 7 or 8) can be based on feedback from switch element junction temperature, heat sink temperature, and / or ambient temperature, to name a few non-limiting examples.

[0085] FIG. 9 illustrates example waveforms 900 in a power delivery system, such as the power delivery system 100 of FIG. 1, operated in accordance with various aspects of the disclosure. As shown in the top plot 902 of FIG. 9, rather than delivering full power during the time that a switch in a solid-state matcher (e.g., matcher 204 of FIG. 2) changes state (i.e., switching from on to off or off to on), the timing of the generator is modified such that the switch changes state during the time 930 when the generator delivers lower power. In some instances, the duration of the low power state (see 930) is extended compared to conventional power systems. For example, a comparison of plot 602 of FIG. 6 and plot 902 of FIG. 9 shows that the duration of the low power state (930) is approximately 3 microseconds longer than in plot 602, which allows for a switch state change to occur during the lower power state.

[0086] Additionally, power delivery to a load (e.g., load 206 in FIG. 2) may be reduced for a period surrounding the time the switch changes state, as shown by 920 and 922 in plot 908. In some circumstances, the reduced power delivery may be due to an increase in reflected power because the total power dissipation in the switch is not a significant fraction of the available power (as depicted by 924 in plot 910).

[0087] In some embodiments, the synchronization scheme illustrated in FIG. 9 may be used for selected periods of time, but not during other times. For example, if PIN diode temperature and / or power dissipation are monitored and used in a feedback loop, the synchronization illustrated by FIG. 9 may be utilized when temperature and / or power dissipation exceed a threshold. Once temperature and / or power dissipation return to acceptable levels, synchronization may be turned off, for example, by returning to a scheme that results in power delivery as shown in FIG. 6. Alternatively, the schemes represented by FIGS. 7, 8, and 9 may be implemented in the same manner as FIG. 6. For example, if the reduced power of FIG. 7 is used initially when a temperature threshold is exceeded, power may be delivered according to FIG. 8 and then FIG. 9 before returning to FIG. 6 (FIG. 9 delivers more power than FIG. 7 but less power than FIG. 6). In other words, the present disclosure can include switching between power delivery schemes as illustrated in Figures 6 and 9 (or 6, 7, 8, and 9) in response to a feedback loop, such as one based on PIN diode switch temperature and / or power dissipation. This alternation between full power (e.g., Figure 6) and reduced power via synchronization (e.g., Figures 7, 8, or 9) can be based on feedback from switch element joint temperature, heat sink temperature, and / or ambient temperature, to name a few non-limiting examples.

[0088] FIG. 10 illustrates an example of a power system 1000 configured for synchronous control in accordance with various aspects of the disclosure. The power system 1000 includes a generator 1002, an SSM 1004, a load 1006, and a synchronization module 1012. The synchronization module 1012 may synchronize the power delivery of the generator 1002 with the operation of the SSM 1004. The load 1006 may be a nonlinear load, such as a plasma load. In some examples, the generator 1004 may be an RF generator. The synchronization module 1012 may be part of either the generator 1002 or the matching network 1004, or may be implemented as a separate unit. In some cases, the generator 1002 applies RF power via a transmission line 1008 (e.g., a coaxial cable) to the matching network 1004 and then via an electrical connection 1010 onto the plasma load 1006. One or more internal components (e.g., variable capacitors) of the SSM 1004 may be varied so that the input impedance of the matching network 1004 matches (or approximately equals) a target input impedance (e.g., 50Ω). As described above, the match or "proximity" between the two impedances may be quantitatively measured using the load reflection coefficient (Γ).

[0089] Most of the time, except when commanded otherwise by the synchronization module 1012, control of the generator 1002 output power is performed via a first control source (e.g., controller 1020). In some cases, the controller 1020 receives user input 1040 (e.g., user input commanding the generator to generate the power waveform 902 of FIG. 9) and / or measured data 1038 obtained through the sensor 1026 and adjusts the control signal 1042 provided to the power amplifier 1024. When commanded by the synchronization module 1012, the control signal 1042 provided to the power amplifier 1024 is transmitted from another control source, such as an amplitude control module 1030 in the synchronization module 1030. In some cases, a third control source (e.g., timing control module 1032) in the synchronization module 1012 helps to adjust the timing of changes in the source of the control signal 1042 via communication 1036. In some cases, changes in the source of the control signal 1042 may be controlled using a switch 1022.

[0090] For example, the switch 1022 in the generator 1002 may be controlled using the timing control module 1032, where controlling the switch includes coupling the power amplifier 1024 to a first control source (e.g., the controller 1020) for a first time period, transitioning control of the power amplifier 1024 from the first control source to a second control source (e.g., the amplitude control 1030), and coupling the power amplifier to the second control source for a second time period. In some cases, the first control source, such as the controller 1020, outputs at least one first control signal (e.g., the control signal 1042). In addition, the second control source outputs at least one second control signal. As described further below, the synchronization module 1012 may obtain timing information 1046 from the SSM 1004. The SSM 1004 may comprise one or more switches. Additionally, the timing information may comprise information regarding the time period when the one or more switches change state, for example, from an open state to a closed state or vice versa. The timing control module 1032 (or alternatively, the synchronization module 1012) may determine a first period during which the first control source is active, a second period during which the second control source is active, and / or a time to switch from the first control source to the second control source or vice versa. In some cases, the synchronization module 1012 receives feedback information related to data measured during one or more of the first and second periods. In addition, the synchronization module 1012 and / or the controller 1020 may adjust one or more of the at least one first control signal and the at least one second control signal based, at least in part, on the feedback information. In some embodiments, the synchronization module 1012 and / or the controller 1020 are configured to one of suspend, reduce, resume, or increase the power delivered by the generator 1002 to the SSM 1004 at or around a period when one or more switches of the SSM change state, as described in further detail below.For example, the power amplifier 1024 may receive an indication to one of suspending, reducing, or increasing the power output for one or more periods when one or more switches of the SSM change state, the indication being received via one of a first control signal (e.g., a control signal received from a first control source, such as the controller 1020) and a second control signal (e.g., a control signal received from a second control source, such as the amplitude control module 1030).

[0091] In some examples, the amplitude control module 1030 may command the power amplifier 1024 to suspend power output for a period of time around the time the switch of the SSM 1004 changes state (depicted by periods 730 and 732 in plot 702 of FIG. 7). The "period of time around the time the switch of the SSM 1004 changes state" (depicted by periods 730 and 732 in plot 702 of FIG. 7) may be determined by several factors, including, but not limited to, the speed at which the power in the generator may be altered (i.e., the speed at which the power amplifier 1024 responds to a change in the control input 1042) and the duration that the switch or switches of the SSM 1004 remain in a high loss state after a state change is initiated. For example, if the generator takes 1 microsecond to cease or reduce power delivery and the switch or switches remain in a high loss state for 3 microseconds, the period around the time the switch of the SSM 1004 changes state may begin 1 microsecond prior to the initiation of the state change of the switch in the SSM 1004 and last for 4 microseconds. Although the power amplifier 1024 is shown with only a control input, the power amplifier 1024 will typically also receive an RF drive signal (e.g., a 13.56 MHz RF signal, not shown), and the output of the power amplifier 1024 may also be interrupted by interrupting the RF drive signal rather than through the control input 1042. In some cases, interrupting the RF drive signal may be a faster way of interrupting power from the power amplifier 1024 and may allow for a shorter interruption of power. Alternatively, the amplitude control module 1030 may command the power amplifier 1024 to reduce power for a period surrounding the time the switch of the SSM 1004 changes state (depicted by periods 830 and 832 in plot 802 of FIG. 8 ). In some cases, the synchronization module 1012 receives feedback regarding the power level during the reduced power period, the feedback information being received via communication 1044 with the generator 1002. In some embodiments, the amplitude control module 1030 utilizes the feedback information to optimize the control signal sent to the power amplifier 1024.

[0092] Additionally or alternatively, the synchronization module 1012 obtains timing information via communications 1044, 1046 with the generator 1002 and the SSM 1004, respectively. In some embodiments, the communications 1044 between the synchronization module 1012 and the generator 1002 and / or the communications 1046 between the synchronization module 1012 and the SSM 1004 may be implemented via dedicated signals (e.g., a signal that changes logic state when a switch in the SSM 1004 changes state, a signal that changes logic state when the generator 1002 changes its power output level), a serial communication means (e.g., an Ethernet link), or a combination thereof. In some aspects, a direct interface between the synchronization module 1012 and the power amplifier's control input 1042 allows for high speed synchronization.

[0093] According to aspects of the disclosure, power delivery by a generator (e.g., generator 1002) to a matching network (e.g., SSM 1004) may be synchronized with the opening and closing of switches in the SSM based, at least in part, on estimating temperatures of devices, switches, etc. in the matching network, as further described below in connection with FIGS. 11-13. In some embodiments, one or more thermal models are utilized to model or estimate one or more of: (1) voltages and / or currents experienced by the switches; (2) power dissipation in the switches; (3) junction temperatures of the switch elements; (4) rise in junction temperature above ambient temperature for one or more switches of the SSM, to name a few non-limiting examples. Additionally, power delivery by the generator may be adjusted based on the estimated / modeled temperatures of devices (e.g., switches) in the SSM. In some examples, power delivery may be suspended or reduced at or around the time when one or more switches of the SSM network change state, e.g., when an estimated temperature exceeds a safety threshold. In some examples, the synchronization module may cause the generator to resume power delivery when one or more switches of the SSM network change state, e.g., at or around the time when an estimated temperature falls below a safety threshold. In some examples, the synchronization module may cause the generator to increase power delivery when one or more switches of the SSM network change state, e.g., at or around the time when an estimated temperature falls below a safety threshold and the generator is in a reduced power state (i.e., outputting less power).

[0094] Turning now to FIG. 11, this illustrates a switch (e.g., switches S1, S2, ..., S of FIG. 3A) according to various aspects of the disclosure. N1 illustrates an example of a thermal model 1100 for a switch. The thermal model 1100 comprises a source 1102 for estimating the power dissipated in the switch. In some examples, the power dissipation may be estimated from measuring or estimating the voltage and current to which the switch is exposed. The thermal model 1100 further includes various thermal resistances, such as thermal resistances 1114 and 1116. Resistor 1114 may be used to model the thermal resistance from a junction to the case of the switch element, such as a PIN diode. Resistor 1116 may be used to model the resistance from a heat sink to the ambient air. Various temperatures may be modeled, including, but not limited to, junction temperature 1104, heat sink temperature 1106, and ambient temperature 1108. Additionally, thermal capacitances may be modeled by capacitors 1110, 1112. Capacitor 1110 may be used to model the thermal capacitance of a semiconductor, such as a die of a PIN diode used in the switch. Additionally, the capacitor 1112 may be used to model the thermal capacity of the heat sink. In some instances, the thermal model 1100 may be used to calculate (or estimate) the junction temperature of the switch elements along with an estimate of the power dissipation 1102.

[0095] 12A illustrates an example dissipation and temperature waveform 1200-a in an SSM of a power delivery system in accordance with various aspects of the disclosure. The top plot 1202 in FIG. 12A shows the switch dissipation (i.e., the power dissipated in one or more switches of the SSM), while plot 1204 depicts the estimated rise in joint temperature above ambient temperature for one or more switches of the SSM.

[0096] In some embodiments, the rise in seam temperature may be calculated or estimated using a thermal model of the device, which may be similar or substantially similar to the thermal model 1100 described in connection with FIG. 11. With an ambient temperature of 55° C. and a maximum safe seam temperature of 125° C., a maximum rise of 70 K may be allowed before steps need to be taken to keep the seam temperature below the safe level of 125° C. Before the seam temperature rise reaches 70 K, the power delivery system may be operated according to the waveform 600 of FIG. 6. Note that the switch power waveform 610 in FIG. 6 may not capture all sources of dissipation in the switch in the SSM. For example, the switch power waveform 610 may only capture a fraction of the RF power that is dissipated in the switch. In addition to RF power, DC power from a driver (e.g., the circuit driving the PIN diode in the switch 400 of FIG. 4) may also be dissipated in the switch. Plot 1212 in Figure 12B depicts both the RF and DC power dissipation in the PIN diodes of the switches in the PIN diode matcher. In addition, plot 1214 in Figure 12B depicts the corresponding increase in junction temperature.

[0097] As shown in plot 1224 of FIG. 12C, the PIN diode junction temperature rise may exceed the 70K safety limit after approximately 54.3 ms. In such a case, the power delivered by the generator may be adjusted so that the generator power delivery waveform resembles or substantially resembles plot 702 in FIG. 7. This adjustment of the generator power helps to reduce the dissipation in the PIN diode. Specifically, changing to the power delivery waveform 702 of FIG. 7 reduces the dissipation in the PIN diode, thus allowing the temperature rise at the PIN diode junction to be reduced, as shown in FIG. 12C.

[0098] Some hysteresis may be employed to switch between waveforms 602 of FIG. 6 and 702 of FIG. 7. In some aspects, this may help reduce the PIN diode junction temperature rise to a lower limit, e.g., about 60K-70K, as shown in plot 1204 of FIG. 12A. However, in some situations, switching between waveforms may not be preferred, e.g., when precision in power delivery is more important. In such cases, the generator power delivery waveform in plot 702 may be utilized instead.

[0099] FIG. 13A illustrates an example dissipation and temperature waveform 1300-a in an SSM of a power delivery system according to various aspects of the disclosure. Plot 1302 illustrates switch dissipation (or power dissipated in a switch of the SSM) versus time. Additionally, plot 1304 illustrates temperature rise (e.g., estimated rise in seam temperature above ambient temperature) versus time. As described above, the rise in seam temperature may be calculated using a thermal model of the device, which may be similar or substantially similar to thermal model 1100 of FIG. 11. With an ambient temperature of 55° C. and a maximum safe seam temperature of 125° C., a maximum rise of 70 K may be allowed before the seam temperature needs to be reduced (e.g., by varying the power delivery waveform for the generator).

[0100] In some embodiments, the power delivery system may be initially operated with the waveform 600 of FIG. 6 (i.e., before the joint temperature rise reaches 70K). Note that the switch power waveform 610 of FIG. 6 may not capture all sources of dissipation in the switch in the PIN diode matcher. For example, the waveform 610 may capture only the RF power fraction that is dissipated in the switch. In addition to RF power, DC power from a driver (e.g., the circuit that drives the PIN diode in the switch 400 of FIG. 4) may also be dissipated in the switch. Plot 1312 in FIG. 13B depicts both RF and DC power dissipation in the PIN diode of the switch in the PIN diode matcher. In addition, plot 1314 in FIG. 13B depicts the corresponding rise in joint temperature.

[0101] As shown in plot 1324 of FIG. 13C, the PIN diode junction temperature rise may exceed the safety limit of 70K after about 52.5 ms. In some embodiments, the power delivered by the generator may be adjusted to reduce the junction temperature rise so that it is below the threshold / safety limit. In one non-limiting embodiment, the power delivered by the generator may be adjusted so that the generator power delivery waveform resembles or substantially resembles plot 802 in FIG. 7. Changing the power delivery waveform 802 helps to reduce the power dissipation in the PIN diode, which in turn helps to reduce the temperature rise of the PIN diode junction. In this case, a reduction in power (e.g., the power levels depicted by 830 and 832 in plot 802) (compared to waveform 1200-c in FIG. 12C) may be controlled to limit the junction temperature rise to <70K. However, in some circumstances, it may not be optional to continually change the power delivery waveform. In such cases, the power delivery system may use fixed power levels, such as power levels 830 and 832 in FIG.

[0102] 14 illustrates an example of a method 1400 for operating a power delivery system according to various aspects of the disclosure. In some embodiments, the operations of the method 1400 may be implemented within the power delivery system 1000 in FIG. 10. In some cases, one or more of the operations described below may be implemented using one or more modules / elements described in connection with FIG. 10, including at least the synchronization module 1012 and the generator 1002.

[0103] The method 1400 begins with delivering power from a generator to a load through a solid-state impedance matching network (operation 1402). The solid-state impedance matching network may be similar or substantially similar to at least any of the SSMs described herein, including SSM 204 in FIG.

[0104] Next, operation 1404 includes synchronizing the opening and closing of the switches in the solid-state impedance matching network with the power delivered from the generator. In some cases, the power delivery system may include a synchronization module (e.g., synchronization module 1012 in FIG. 10), which may include one or more of an amplitude control module (e.g., amplitude control module 1030 in FIG. 10) and a timing control module (e.g., timing control module 1032). In some examples, the amplitude control module and the timing control module may be implemented as a single control module. In addition, the synchronization module, including its sub-modules, may be embodied in hardware, software, or a combination thereof.

[0105] In some cases, in operation 1406, the method 1400 includes halting power delivery from the generator for at least a period of time around the opening and closing of the switches in the solid-state impedance matching network. As described in connection with FIG. 10, the amplitude control module 1030 in the synchronization module 1012 may command (e.g., via communication 1034) the power amplifier 1024 to pause / stop the power output for a period of time around the time the switches of the solid-state impedance matching network change state. In this way, power delivery from the generator to a load (e.g., a plasma load) can be stopped around the time when the switches of the SSM are opened and closed. In some aspects, such a design helps to (1) minimize or reduce power dissipation in the switches and (2) control the junction temperature rise in the switches (or PIN diodes used to implement the switches) so that it is below a threshold / safety limit. In addition, pausing or stopping power delivery around the time when the switches are opened and closed has little or no effect on the average and total power delivered by the generator to the load. However, the reduction in power dissipation in the switch helps to improve the efficiency of the power delivery system as compared to the prior art. Stopping power delivery is illustrated by, but is not limited to, the example shown in FIG. 7, and normal power delivery is illustrated by, but is not limited to, the example shown in FIG. 6.

[0106] 15 illustrates an example of a method 1500 for operating a power delivery system according to various aspects of the disclosure. In some embodiments, the operations of the method 1500 may be implemented within the power delivery system 1000 in FIG. 10. In some cases, one or more of the operations described below may be implemented using one or more modules / elements described in connection with FIG. 10, including at least the synchronization module 1012 and the generator 1002.

[0107] In operation 1502, the method 1500 includes delivering power from a generator (e.g., generator 1002) to a load (e.g., load 1006, which may be a plasma load) through a solid-state impedance matching network (e.g., SSM 1004).

[0108] Next, operation 1504 includes synchronizing the opening and closing of switches in a solid-state impedance matching network with the power delivered from the generator.

[0109] Finally, operation 1506 includes reducing power delivery from the generator for at least one period of time surrounding the opening and closing of the switches in the solid-state impedance matching network.

[0110] Reduced power delivery is illustrated by, but is not limited to, the examples shown in FIGS. 8 and 9, and normal power delivery is illustrated by, but is not limited to, the example shown in FIG.

[0111] 16 illustrates an example of a method 1600 for operating a power delivery system according to various aspects of the disclosure. In some embodiments, the operations of the method 1600 may be implemented within the power delivery system 1000 in FIG. 10. In some cases, one or more of the operations described below may be implemented using one or more modules / elements described in connection with FIG. 10, including at least the synchronization module 1012 and the generator 1002.

[0112] The method 1600 begins with delivering power from a generator to a load through a solid-state impedance matching network (operation 1602). The power delivered from the generator is then synchronized with the opening and closing of switches in the solid-state impedance matching network (operation 1604). The temperature of a component (e.g., a PIN diode switch) in the solid-state impedance matching network is then estimated (operation 1606). In some embodiments, the temperature of the component may be estimated using the thermal model 1100 described above in connection with FIG. 11. In some examples, if the temperature of the component exceeds an upper threshold (e.g., >125° C., >70° C. above ambient temperature, where the ambient temperature may be 55° C., to name two non-limiting examples), the power delivery from the generator is stopped for one or more periods of time surrounding the time when the switch in the solid-state impedance matching network is opened and closed.

[0113] In some circumstances, suspending (or at least reducing) power delivery from the generator can help reduce the temperature of a component (e.g., a PIN diode) so that it drops below a safety threshold. In some cases, for example, once the temperature falls below an upper threshold, operation 1610 includes resuming power delivery from the generator for at least one period around when a switch in the solid-state impedance matching network is opened and closed.

[0114] As seen in FIG. 16, one or more of operations 1606, 1608, and 1610 may be repeated as long as the generator (eg, an RF generator) delivers power to the load.

[0115] Stopping power delivery is illustrated by, but not limited to, the example shown in FIG. 7, and normal power delivery is illustrated by, but not limited to, the example shown in FIG.

[0116] 17 illustrates an example of a method 1700 for operating a power delivery system according to various aspects of the disclosure. In some embodiments, the operations of the method 1700 may be implemented within the power delivery system 1000 in FIG. 10. In some cases, one or more of the operations described below may be implemented using one or more modules / elements described in connection with FIG. 10, including at least the synchronization module 1012 and the generator 1002.

[0117] In operation 1702, the method 1700 includes delivering power from a generator (eg, generator 1002) to a load (eg, load 1006) through a solid-state impedance matching network (eg, SSM 1004).

[0118] Operation 1704 includes synchronizing the opening and closing of switches in a solid-state impedance matching network with the power delivered from the generator.

[0119] Operation 1706 includes estimating temperatures of components in the solid-state impedance matching network (e.g., using a thermal model such as PIN diode thermal model 1100). Some non-limiting examples of components may include a switch, a PIN diode, a switch with at least one PIN diode, a PIN diode junction, and a heat sink. Note that in some embodiments, various temperatures may be modeled / estimated using one or more thermal models. In some embodiments, one or more of a switch element junction temperature, a heat sink temperature, and / or an ambient temperature may be modeled or estimated in operation 1706.

[0120] Next, in operation 1708, the method 1700 includes reducing power delivery from the generator for at least one period of time surrounding when the switches in the solid-state impedance matching network are opened / closed, the power reduction being based, at least in part, on determining that the temperature estimated in operation 1706 exceeds a threshold value (e.g., a safety limit for the component).

[0121] As explained above, reducing the power delivery at or around the time the switch changes state (i.e., is opened or closed) helps to reduce or halt the temperature rise of the component. Furthermore, the temperature of the component may be reduced so that it is below a safety limit / threshold. In such a case, in operation 1710, the method includes increasing the power delivery from the generator for at least one period of time around when the switch in the solid-state impedance matching network opens / closes. In some cases, operation 1710 may be performed when the temperature of the component (e.g., the PIN diode) is below a threshold, the generator power is in a reduced state (e.g., 820 and 822 in FIG. 8), or a combination thereof.

[0122] Similar to the method 1600, in some embodiments, the operations 1706, 1708, and 1710 may be repeated as long as power is being delivered to the load.

[0123] Reducing power delivery is illustrated by, but not limited to, the examples shown in Figures 8 and 9, and normal power delivery is illustrated by, but not limited to, the example shown in Figure 6. Although not shown, methods 1600 and 1700 can be combined such that power is stopped or reduced depending on the feedback. For example, power can be reduced (1708 in Figure 17) if a characteristic of the feedback (e.g., PIN diode junction temperature) exceeds a threshold, and stopped if the feedback continues in the same direction and exceeds a second threshold that is above the first threshold. Or, a hysteresis method can be implemented in which power is stopped when the first threshold is exceeded, but the power can be increased slightly, but not completely, as the feedback returns toward the threshold (e.g., 1708 in Figure 17 and schemes of Figures 7 or 8). Only after the feedback drops below the threshold can power be fully resumed (e.g., block 1610 and schemes of Figure 6).

[0124] FIG. 18 illustrates a block diagram of a computer system 1800 that may be used to implement one or more aspects of the disclosure, including at least a method for synchronizing power delivery by a generator to a matcher network (e.g., as described above in connection with FIGS. 14-17). As shown, in this embodiment, a display 1812 and a non-volatile memory 1829 are coupled to a bus 1822, which is also coupled to a random access memory ("RAM") 1824, a processing portion 1826 (including N processing components), a field programmable gate array (FPGA) 1827, and a transceiver component 1828 including N transceivers. Although the components depicted in FIG. 18 represent physical components, FIG. 18 is not intended to be a detailed hardware diagram, and thus many of the components depicted in FIG. 18 may be realized by common construction or distributed among additional physical components. Other existing and yet to be developed physical components and architectures may also be utilized to implement the functional components described with reference to FIG. 18.

[0125] The display 1812 generally operates to provide a user interface for a user, and in some implementations, the display 1812 is realized by a touch screen display. For example, the display 1812 can be used to control and interact with the components described herein. In general, the non-volatile memory 1829 is a non-transient memory that functions to store (e.g., persistently store) data and machine-readable (e.g., processor-executable) code (including executable code associated with effecting the methods described herein). In some embodiments, for example, the non-volatile memory 1829 includes boot loader code, operating system code, file system code, and non-transient processor-executable code to facilitate execution of the methods described herein, such as methods 1400-1700 of FIGS. 14-17.

[0126] In some implementations, non-volatile memory 1829 may be realized by flash memory (e.g., NAND or ONENAND memory). In other embodiments, other memory types may be utilized as well. While some embodiments may execute code from non-volatile memory 1829, in other embodiments, executable code in non-volatile memory may typically be loaded into RAM 1824 and executed by one or more of the N processing components in processing portion 1826.

[0127] In operation, the N processing components associated with the RAM 1824 may generally operate to execute instructions stored in the non-volatile memory 1829 to effectuate the functionality of the power delivery system described herein, including at least a synchronization module (e.g., synchronization module 112, synchronization module 1012), a controller (e.g., controller 1020), and / or a generator (e.g., generator 102, generator 1002). For example, non-transient processor executable instructions for effecting the methods described herein may be persistently stored in the non-volatile memory 1829 and executed by the N processing components associated with the RAM 1824. The processing portion 1826 may include a video processor, a digital signal processor (DSP), a graphics processing unit (GPU), and other processing components.

[0128] Additionally, or in other embodiments, a field programmable gate array (FPGA) 1827 may be configured to effect one or more aspects of the methodologies described herein. For example, non-transient FPGA configuration instructions may be persistently stored in non-volatile memory 1829 and accessed by FPGA 1827 (e.g., during power-up) to configure FPGA 1827.

[0129] The input component 1831 may generally operate to receive signals (e.g., user input 1040, measured data 1038, feedback information 1044, timing information 1046, to name a few). Additionally, the output component 1832 may generally operate to provide one or more digital and / or analog signals (e.g., communications specific to amplitude control 1034, communications specific to timing control 1036, control signals input to the power amplifier 1042, to name a few) to effect operational aspects of the power delivery system and / or other systems described herein. In some embodiments, the computer system 1800 may be configured to implement a method for operating a power delivery system including at least synchronizing the opening and closing of switches in a solid-state impedance matching network with power delivered from a generator, as described above with respect to Figures 1-2, 7-8, 10, and 14-17.

[0130] The depicted transceiver component 1828 includes N transceiver chains that may be used to communicate with external devices (e.g., an external controller) over a wireless or wired network. Each of the N transceiver chains may represent a transceiver associated with a particular communication scheme (e.g., Wifi, Ethernet, Profibus, etc.).

[0131] Methods 1400-1700, as well as other methods of the present disclosure, may include other steps or transitions in various other embodiments. Some or all of any of methods 1400-1700 may be performed by or embodied in hardware in controlling other associated hardware, devices, systems, or products in performing, implementing, or embodying various subject matter of the methods, and / or performed or executed by a measurement and control multiprocessor system-on-chip (MPSoC), which may include a controller, CPU, FPGA, system-on-chip (SoC), both a CPU and FPGA, and other elements together within one integrated SoC or other processing or computing device processing executable instructions. Additional Embodiments

[0132] Some aspects of the disclosure may be characterized as a method for operating a power delivery system, the method including connecting a generator to a solid-state matching network, delivering power to the solid-state matching network with the generator, and synchronizing the power with the opening and closing of switches in the solid-state impedance matching network.

[0133] In some implementations of the methods described above, the power delivered by the generator to the solid-state matching network is stopped for a period surrounding the opening and closing of a switch in the solid-state matching network.

[0134] In some implementations of the methods described above, the power delivered by the generator to the solid-state matching network is reduced for the time surrounding the opening and closing of switches in the solid-state matching network.

[0135] In some implementations of the methods described above, the power delivered by the generator to the solid-state matching network is reduced for a period surrounding the opening and closing of a switch in the solid-state matching network.

[0136] In some implementations, the method further includes estimating a temperature of a device (e.g., a switch) in the solid-state matching network, and when the temperature exceeds an upper threshold (e.g., a safety threshold), stopping power delivered by the generator to the solid-state matching network for a period surrounding the opening and closing of the switch in the solid-state matching network.

[0137] In some implementations, the method further includes resuming power delivered by the generator to the matching network for a period surrounding the opening and closing of the switch in the solid-state matching network when the temperature falls below an upper limit or safety threshold.

[0138] In some implementations, the method further includes estimating a temperature of a device, such as a switch, in the solid-state matching network, and reducing the power delivered by the generator to the solid-state matching network for a period surrounding the opening and closing of the switch in the solid-state matching network when the temperature exceeds a threshold (e.g., an upper limit or safety threshold for safe operation of a switch, such as a PIN diode switch).

[0139] In some implementations, the method further includes increasing the power delivered by the generator to the matching network for a period surrounding the opening and closing of a switch in the solid-state matching network when the temperature falls below a safety threshold and the power output from the generator is currently reduced.

[0140] In some implementations, the method further includes connecting the solid-state matching network to a load (eg, a nonlinear load, such as a plasma load).

[0141] As used herein, the recitation of "at least one of A, B, and C" is intended to mean "any of A, B, C, or any combination of A, B, and C." The foregoing description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the spirit or scope of the present disclosure. Thus, the present disclosure is not intended to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0142] Terms such as "first," "second," "third," and the like may be used herein to describe various elements, components, regions, layers, and / or sections, but it should be understood that these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Thus, a first element, component, region, layer, or section discussed below may also be referred to as a second element, component, region, layer, or section without departing from the teachings of the present disclosure.

[0143] Spatially relative terms such as "below," "below," "below side," "down," "above," "upper," and the like may be used herein to describe the relationship of one element or feature to another element or feature as illustrated in the figures for ease of description. It should be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures were turned over, elements described as being "below," or "below," or "below" the other element or feature would therefore be oriented "above" the other element or feature. Thus, the exemplary terms "below" and "below" can encompass both "upper" and "lower" orientations. The device may be oriented differently (e.g., rotated 90 degrees or in other orientations) and the spatially relative descriptors used herein may be interpreted accordingly. Additionally, it should also be understood that when a layer is referred to as being "between" two layers, this may be the only layer between the two layers, or one or more intervening layers may also be present.

[0144] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It is further understood that the terms "comprises" and / or "comprising", as used herein, specify the presence of the stated features, integers, steps, operations, elements, components, and / or groups, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. As used herein, the term "and / or" includes any combination of one or more of the associated listed items and may be abbreviated as " / ".

[0145] When an element or layer is referred to as being "on", "connected to", "coupled to", or "adjacent to" another element or layer, it is understood that it may be "directly on", "connected to", "coupled to", or "adjacent to" the other element or layer, or there may be intervening elements or layers. In contrast, when an element is referred to as being "directly on", "directly connected to", "directly coupled to", or "directly adjacent to" another element or layer, no intervening elements or layers are present.

[0146] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art to which this disclosure belongs. It is further understood that terms such as those defined in commonly used dictionaries should be interpreted to have a meaning consistent with their meaning in the relevant field and / or in the context of this specification, and will not be interpreted in an idealized or overly formal sense unless expressly defined as such in this specification.

Claims

1. 1. A power delivery system comprising: a solid-state matcher (SSM) network having a load side and a source side and one or more switches therebetween; a generator connected to a source side of the SSM network; a plurality of control sources for controlling power delivered by the generator to the SSM network, the plurality of control sources including at least a first control source configured to output a first control signal and a second control source configured to output a second control signal; a synchronization module coupled to the generator and to the SSM network, the synchronization module comprising: obtaining timing information from the SSM network, the timing information comprising information regarding a period when one or more switches of the SSM network change state from an open state to a closed state or vice versa; and synchronizing power delivered by the generator to the SSM network based at least in part on the timing information, the synchronizing comprising: selecting one of the first control source and the second control source for connection to the generator; one of suspending, reducing, resuming, or increasing power delivered by the generator to the SSM network at or around the time period when one or more switches of the SSM network change state; Including, a synchronization module configured to:

1. A power delivery system comprising:

2. 10. The power delivery system of claim 1, wherein the generator comprises the first control source and the synchronization module comprises the second control source for amplitude control.

3. 3. The power delivery system of claim 2, wherein when the second controlled source is connected to the generator, the synchronization module is configured to suspend power delivered by the generator to the SSM network for a period surrounding when one or more switches of the SSM network change state.

4. 3. The power delivery system of claim 2, wherein when the second controlled source is connected to the generator, the synchronization module is configured to reduce power delivered by the generator to the SSM network for a period surrounding when one or more switches of the SSM network change state.

5. The synchronization module further comprises: estimating a temperature of at least one device in the SSM network; comparing the temperature to a threshold value; transmitting an indication to the generator to suspend power delivery to the SSM matching network for at least one period of time at or around when one or more switches of the SSM network change state when the temperature exceeds the threshold; The power delivery system of claim 2 configured to:

6. 6. The power delivery system of claim 5, wherein the synchronization module is further configured, at least in part, based on detecting the temperature falling below the threshold, to transmit another indication to the generator to resume power delivery to the SSM network for at least one period at or around when one or more switches of the SSM network change state.

7. The synchronization module further comprises: estimating a temperature of at least one device in the SSM network; comparing the temperature to a threshold value; transmitting an indication to the generator to reduce power delivery to the SSM matching network for at least one period of time at or around when one or more switches of the SSM network change state when the temperature exceeds the threshold; The power delivery system of claim 1 configured to:

8. 8. The power delivery system of claim 7, wherein the synchronization module is further configured, at least in part, based on detecting the temperature falling below the threshold, to transmit another indication to the generator to increase power delivery to the SSM network at or for at least one period around when one or more switches of the SSM network change state.

9. 8. The power delivery system of claim 7, further comprising a plasma load connected to the SSM network.

10. 8. The power delivery system of claim 7, wherein the generator comprises the first control source, and the synchronization module comprises the second control source for amplitude control and a third control source for timing control, the third control source adjusting a timing for connecting one of the first control source and the second control source to a power amplifier of the generator and disconnecting another of the first control source and the second control source from the power amplifier.

11. A synchronization module, comprising: One or more hardware processors, the one or more hardware processors configured by machine readable instructions to: identifying a first control source, the first control source outputting at least one first control signal; identifying a second control source, the second control source outputting at least one second control signal; obtaining timing information from a solid-state matching network, the solid-state matching network comprising one or more switches, the timing information comprising information regarding time periods when the one or more switches change state; Based at least in part on the timing information, a first period during which the first control source is active; and a second period during which the second control source is active; and the time for switching from the first control source to the second control source or vice versa; determining two or more of the one or more hardware processors configured to A synchronization module comprising:

12. The one or more hardware processors are further configured to execute machine readable instructions to: receiving feedback information relating to data measured during one or more of the first time period and the second time period; adjusting one or more of the at least one first control signal and the at least one second control signal based at least in part on the feedback information; The synchronization module of claim 11 configured to:

13. The synchronization module is electronically, logically, or communicatively coupled to a generator and to the solid-state matching network, the generator comprising: a power amplifier configured to receive the at least one first control signal from the first control source and the at least one second control signal from the second control source; At least one switch The synchronization module of claim 11 , comprising:

14. The one or more hardware processors are further configured to execute machine readable instructions to: Controlling the at least one switch in the generator, the controlling the at least one switch in the generator comprising: coupling the power amplifier to the first control source for the first time period; transitioning control of the power amplifier from the first control source to the second control source; coupling the power amplifier to the second control source during the second time period; Including The synchronization module of claim 13 configured to:

15. The one or more hardware processors are further configured to execute machine readable instructions to: transmitting an indication to the power amplifier to one of suspend, reduce, or increase a power output for each of the one or more time periods when one or more switches of the solid-state matching network change state, the indication being received via one of the first control signal and the second control signal; The synchronization module of claim 14 configured to:

16. The one or more hardware processors are further configured to execute machine readable instructions to: receiving feedback information related to a power level measured during at least one duration when power output from the power amplifier is paused, reduced, or increased; adjusting one or more of the at least one first control signal, the at least one second control signal, the first period, and the second period based at least in part on the feedback information; The synchronization module of claim 15 configured to:

17. 1. A non-transitory tangible computer readable storage medium encoded with processor readable instructions for performing a method for operating a power delivery system, the method comprising: identifying a first control source, the first control source outputting at least one first control signal; identifying a second control source, the second control source outputting at least one second control signal; obtaining timing information from a solid-state matching network, the solid-state matching network comprising one or more switches, the timing information comprising information regarding a period when the one or more switches change state from an open state to a closed state or vice versa; Based at least in part on the timing information, a first period during which the first control source is active; and a second period during which the second control source is active; and the time for switching from the first control source to the second control source or vice versa; determining two or more of the 16. A non-transitory tangible computer readable storage medium comprising:

18. The solid state matching network is connected to a generator, the method further comprising: synchronizing power delivery by the generator to the solid-state matching network based at least in part on the timing information, said synchronizing comprising: selecting one of the first control source and the second control source for connection to the generator; one of suspending, reducing, resuming, or increasing power delivered by said generator to said solid-state matching network at or around said period when one or more switches of said solid-state matching network change state; Including, 20. The non-transitory tangible computer readable storage medium of claim 17, comprising:

19. The method further comprises: receiving feedback information relating to data measured during one or more of the first time period and the second time period; adjusting one or more of the at least one first control signal and the at least one second control signal based at least in part on the feedback information; 20. The non-transitory tangible computer readable storage medium of claim 17, comprising:

20. The method further comprises: connecting said solid state matching network to a plasma load; 20. The non-transitory tangible computer readable storage medium of claim 17, comprising:

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