Abstract: A RF amplifier is provided that includes a plurality of switch modules connected in a cascade configuration and divided into disjoint sets in accordance with their corresponding distinct peak DC voltages or currents, each switch module including a plurality of switch devices connected in a half-bridge or full-bridge circuit and a DC voltage or current source electrically connected with the half-bridge or full-bridge circuit, and a control circuit configured to determine an output voltage or current of the RF amplifier at the next switching interval, examine the states of the switching devices in the respective switch modules to identify a combination of least-recently-switched switching devices within each set of switch modules that, when switched to an opposite state, will produce the determined output voltage or current, and switch to an opposite state, at the next switching interval, the switching devices in the identified combination.

Abstract: A generator and method for tuning the generator are disclosed. The method includes setting the frequency of power applied by the generator to a current best frequency and sensing a characteristic of the power applied by the generator. A current best error based upon the characteristic of the power is determined, and the frequency of the power at the current best frequency is maintained for a main-time-period. The frequency of the power is then changed to a probe frequency and maintained at the probe frequency for a probe-time-period, which is less than the main-time-period. The current best frequency is set to the probe frequency if the error at the probe frequency is less than the error at the current best frequency.

Abstract: A radio-frequency (RF) generator is provided that produces a controlled overshoot. One embodiment includes a RF power amplifier and a direct-current (DC) power supply that includes a primary DC power supply, an auxiliary DC power supply, a half-bridge circuit, and a control circuit. The half-bridge circuit, in a first switching state, electrically connects, in series, the auxiliary DC power supply with the primary DC power supply and, in a second switching state, electrically disconnects the auxiliary DC power supply from the primary DC power supply. The control circuit places the half-bridge circuit in the first switching state for a first period of time and places the half-bridge circuit in the second switching state for a second period of time to produce a controlled overshoot in the power produced by the RF generator throughout the first period of time.

Abstract: Systems and methods for adjusting the source impedance of a generator are disclosed. An exemplary method includes generating a first signal and applying the first signal to a first input of a combiner, generating a second signal and applying the second signal to a second input of said combiner, and combining the first and second signals with the combiner at an output of the combiner to produce power that is delivered to the plasma load. A controllable variable impedance is provided to an isolation port of the combiner, and the controllable variable impedance is adjusted to vary the source impedance of the generator.

Abstract: This disclosure describes systems, methods, and apparatuses for impedance-matching radio frequency power transmitted from a radio frequency generator to a plasma load in a semiconductor processing chamber. Impedance-matching can be performed via a match network having a variable-reactance circuit. The variable-reactance circuit can comprise one or more reactive elements all connected to a first terminal and selectively shorted to a second terminal via a switch. The switch can comprise a bipolar junction transistor (BJT) or insulated gate bipolar transistor (IGBT) controlled via bias circuitry. In an on-state, the BJT base-emitter junction is forward biased, and AC is conducted between a collector terminal and a base terminal. Thus, AC passes through the BJT primarily from collector to base rather than from collector to emitter. Furthermore, the classic match network topology used with vacuum variable capacitors can be modified such that voltages do not overload the BJT's in the modified topology.

Abstract: A radio-frequency (RF) generator is provided that produces a controlled overshoot. One embodiment includes a RF power amplifier and a direct-current (DC) power supply that includes a primary DC power supply, an auxiliary DC power supply, a half-bridge circuit, and a control circuit. The half-bridge circuit, in a first switching state, electrically connects, in series, the auxiliary DC power supply with the primary DC power supply and, in a second switching state, electrically disconnects the auxiliary DC power supply from the primary DC power supply. The control circuit places the half-bridge circuit in the first switching state for a first period of time and places the half-bridge circuit in the second switching state for a second period of time to produce a controlled overshoot in the power produced by the RF generator throughout the first period of time.

Abstract: A power generation system and method for identifying characteristics of a plasma load are disclosed. The power generation system may include a power source configured to apply a primary power signal at a primary frequency to an output and one or more secondary power signals at one or more secondary frequencies to the output. A sensor is arranged to monitor a characteristic of the power delivered to the plasma load, and an identification module analyzes the monitored characteristic to extract characteristics of the plasma load.

Abstract: This disclosure describes systems, methods, and apparatus for ensuring desirable ignition of plasma in a plasma processing chamber via providing increased instantaneous power during an ignition period for both continuous wave (CW) and pulsed power delivery. The systems, methods, and apparatus can be applied to both initial ignition of a plasma and reignition of a plasma where pulsed power delivery leads to periodic extinction of the plasma.

Abstract: This disclosure describes a switch having a collector, base, emitter, and an intrinsic region between the collector and base. The intrinsic region increases the efficiency of the switch and reduces losses. The collector, base, and emitter each have respective terminals, and an AC component of current passing through the base terminal is greater than an AC component of current passing through the emitter terminal. Additionally, in an on-state a first alternating current between the base and collector terminals is greater than a second alternating current between the collector and emitter terminals. In other words, AC passes primarily between collector and base as controlled by a DC current between the base and emitter.

Abstract: A generator and method for tuning the generator are disclosed. The method includes setting the frequency of power applied by the generator to a current best frequency and sensing a characteristic of the power applied by the generator. A current best error based upon the characteristic of the power is determined, and the frequency of the power at the current best frequency is maintained for a main-time-period. The frequency of the power is then changed to a probe frequency and maintained at the probe frequency for a probe-time-period, which is less than the main-time-period. The current best frequency is set to the probe frequency if the error at the probe frequency is less than the error at the current best frequency.

Abstract: This disclosure describes systems, methods, and apparatus for frequency tuning a power source so as to optimize power delivery to a plasma load as well as systems, methods, and apparatus for identifying characteristics and/or changes in characteristics of a plasma load. In particular, a secondary power signal can be applied concurrently with a primary power signal, the secondary power signal having a substantially lower power level, so as to tune for a global optimum of a measure of performance and/or identifying characteristics and/or changes in characteristics of a plasma load. The secondary power signal can comprise a low level signal that is jointly generated with or combined with the primary power signal, or it can comprise noise either inherent to the primary power signal or added to the primary power signal.

Abstract: A power generation system and method for identifying characteristics of a plasma load are disclosed. The power generation system may include a power source configured to apply a primary power signal at a primary frequency to an output and one or more secondary power signals at one or more secondary frequencies to the output. A sensor is arranged to monitor a characteristic of the power delivered to the plasma load, and an identification module analyzes the monitored characteristic to extract characteristics of the plasma load.

Abstract: A generator and method for tuning the generator are disclosed. The method includes setting the frequency of power applied by the generator to a current best frequency and sensing a characteristic of the power applied by the generator. A current best error based upon the characteristic of the power is determined, and the frequency of the power at the current best frequency is maintained for a main-time-period. The frequency of the power is then changed to a probe frequency and maintained at the probe frequency for a probe-time-period, which is less than the main-time-period. The current best frequency is set to the probe frequency if the error at the probe frequency is less than the error at the current best frequency.

Abstract: A method and generator for modifying interactions between a load and the generator are described. The method includes applying output power to the load using a power amplifier, controlling a level of the output power responsive to a power control setting, and adjusting a conduction angle of the power amplifier to reduce a level of sensitivity of the power amplifier to variations of an impedance of the load. The generator includes a compensation subsystem coupled to the power amplifier that controls a conduction angle of the power amplifier to enable a sensitivity of the power amplifier to be adjusted.

Abstract: This disclosure describes systems, methods, and apparatuses for impedance-matching radio frequency power transmitted from a radio frequency generator to a plasma load in a semiconductor processing chamber. Impedance-matching can be performed via a match network having a variable-reactance circuit. The variable-reactance circuit can comprise one or more reactive elements all connected to a first terminal and selectively shorted to a second terminal via a switch. The switch can comprise a bipolar junction transistor (BJT) or insulated gate bipolar transistor (IGBT) controlled via bias circuitry. In an on-state, the BJT base-emitter junction is forward biased, and AC is conducted between a collector terminal and a base terminal. Thus, AC passes through the BJT primarily from collector to base rather than from collector to emitter. Furthermore, the classic match network topology used with vacuum variable capacitors can be modified such that voltages do not overload the BJT's in the modified topology.

Abstract: Systems and methods for adjusting the source impedance of a generator are disclosed. An exemplary method includes generating a first signal and applying the first signal to a first input of a combiner, generating a second signal and applying the second signal to a second input of said combiner, and combining the first and second signals with the combiner at an output of the combiner to produce power that is delivered to the plasma load. A controllable variable impedance is provided to an isolation port of the combiner, and the controllable variable impedance is adjusted to vary the source impedance of the generator.

Abstract: This disclosure describes systems, methods, and apparatus for ensuring desirable ignition of plasma in a plasma processing chamber via providing increased instantaneous power during an ignition period for both continuous wave (CW) and pulsed power delivery. The systems, methods, and apparatus can be applied to both initial ignition of a plasma and reignition of a plasma where pulsed power delivery leads to periodic extinction of the plasma.

Abstract: This disclosure describes a switch having a collector, base, emitter, and an intrinsic region between the collector and base. The intrinsic region increases the efficiency of the switch and reduces losses. The collector, base, and emitter each have respective terminals, and an AC component of current passing through the base terminal is greater than an AC component of current passing through the emitter terminal. Additionally, in an on-state a first alternating current between the base and collector terminals is greater than a second alternating current between the collector and emitter terminals. In other words, AC passes primarily between collector and base as controlled by a DC current between the base and emitter.

Abstract: A generator and method for tuning the generator are disclosed. The method includes setting the frequency of power applied by the generator to a current best frequency and sensing a characteristic of the power applied by the generator. A current best error based upon the characteristic of the power is determined, and the frequency of the power at the current best frequency is maintained for a main-time-period. The frequency of the power is then changed to a probe frequency and maintained at the probe frequency for a probe-time-period, which is less than the main-time-period. The current best frequency is set to the probe frequency if the error at the probe frequency is less than the error at the current best frequency.

Abstract: A method and generator for modifying interactions between a load and the generator are described. The method includes applying output power to the load using a power amplifier, controlling a level of the output power responsive to a power control setting, and adjusting a conduction angle of the power amplifier to reduce a level of sensitivity of the power amplifier to variations of an impedance of the load. The generator includes a compensation subsystem coupled to the power amplifier that controls a conduction angle of the power amplifier to enable a sensitivity of the power amplifier to be adjusted.