Systems and methods for synchronization of radio frequency (RF) pulsing schemes and of sensor data collection are described. One of the methods includes receiving, by an RF generator, a first set of one or more variable levels and one or more duty cycles of an RF signal. The method further includes receiving, by the RF generator from a pulse controller, a synchronization signal having a plurality of pulses. The method also includes generating, during a clock cycle of a clock signal, multiple instances of a first plurality of states of the RF signal in synchronization with the plurality of pulses of the synchronization signal. Each of the first plurality of states of the RF signal has a corresponding one of the one or more variable levels of the first set and a corresponding one of the one or more duty cycles of the first set.

A method for controlling a critical dimension of a mask layer is described. The method includes receiving a first primary parameter level, a second primary parameter level, a first secondary parameter level, a second secondary parameter level, and a third secondary parameter level. The method also includes generating a primary signal having the first primary parameter level, and transitioning the primary signal from the first primary parameter level to the second primary parameter level. The method further includes generating a secondary radio frequency (RF) signal having the first secondary parameter level, and transitioning the secondary RF signal from the first secondary parameter level to the second secondary parameter level. The method includes transitioning the secondary RF signal from the second secondary parameter level to the third secondary parameter level.

A power supply system controls the source impedance of a generator utilizing two amplifiers having asymmetrical power profiles in reference to a nominal load impedance that are diametrically opposite in reference to the nominal load impedance. Variations in power profiles may be achieved by using different topologies for each of the amplifiers or implementing a phase delay network. The output power from the first and second amplifiers may be combined using a combiner circuit or device and the output power from the combiner is transmitted to a plasma load. The output power of each amplifier may be independently controlled to alter one or more characteristics of the output power signal provided by the individual amplifiers. By changing the ratio of the output power of the first amplifier to the output power of the second amplified, the source impedance of the generators may be varied.

A disclosed etching method includes (a) generating plasma of a processing gas in a chamber of a plasma processing apparatus. The plasma is generated in a state where a substrate is placed on a substrate support having a lower electrode in the chamber. The substrate has a film and a mask. The mask is provided on the film. The etching method further includes (b) etching the film by supplying ions from the plasma to the substrate by periodically applying a pulse of a voltage to a lower electrode. In the operation (b), a level of a voltage of the pulse is changed at least once such that an absolute value of a negative potential of the substrate has a tendency to increase according to progress of etching of the film.

A radio frequency (RF) generator includes a pulse generator circuit configured to receive input signals indicative of a pulse pattern comprising pulse segments, the input signals defining power levels and durations for the pulse segments. The pulse generator circuit generates a pulse modulation control signal for each pulse segment responsive to the input signals. The pulse modulation control signal is coupled to adjust an amplitude and to modulate an RF source signal to generate the pulse RF signal having an envelope defined by the pulse segments of the pulse pattern.

A variable frequency and non-sinusoidal power generator includes a pulse module circuit, a slope module circuit, and first and second cooling systems. The pulse module circuit and the slope module circuit includes control switches, and generates at least one of a output currents and a output voltages by selectively turning on/off the control switches based on control signals. The first and second cooling systems are disposed at first and second sides of the control switches. A bias power having a variable frequency and a non-sinusoidal waveform is generated based on the control signals, at least one of the output currents and the output voltages.

A method of performing pulsed remote plasma etching includes arranging a substrate in a processing chamber configured to perform pulsed remote plasma etching, setting at least one process parameter of the processing chamber, supplying at least one gas mixture to an upper chamber region of the processing chamber, supplying, in an ON period, a first voltage to coils arranged around the upper chamber region to energize the at least one gas mixture and generate plasma within the upper chamber region of the processing chamber, turning off the first voltage in an OFF period to discontinue generating plasma within the upper chamber region of the processing chamber, and alternating between supplying the first voltage in the ON period and turning off the first voltage in the OFF period to generate pulsed remote plasma within the upper chamber region of the processing chamber.

A method for pulsing is described. The method includes generating a first radio frequency (RF) signal, and pulsing a parameter of the first RF signal between a first parameter level and a second parameter level at a pulsing frequency during a cycle of a digital pulsed signal. The method further includes generating a second RF signal, and pulsing a parameter of the second RF signal at a higher pulsing frequency than the pulsing frequency of the parameter of the first RF signal during the cycle. During the cycle, a start time of pulsing the parameter of the first RF signal is synchronized with a start time of pulsing the parameter of the second RF signal and an end time of pulsing the parameter of the first RF signal is synchronized with an end time of pulsing the parameter of the second RF signal.

In some implementations, a method for performing a plasma process in a chamber is provided, including: supplying a process gas to the chamber; applying pulsed RF power to the process gas in the chamber, the pulsed RF power being provided at a predefined frequency, wherein the applying of the pulsed RF power to the process gas generates a plasma in the chamber; during the applying of the RF power, applying a pulsed DC current to a magnetic coil that is disposed over the chamber, wherein the pulsed DC current is provided at the predefined frequency.

A radio frequency (RF) generator includes a RF power source configured to output an RF power signal, and a controller coupled to the RF power source. The controller is configured to generate a pulse to modulate the RF power signal of the RF power source. The pulse includes one or more state transitions. The controller is further configured to receive a sync signal indicative of one or more operating characteristics or parameters of another RF generator, and adjust at least one of the state transitions of the pulse to synchronize the state transition with a defined phase of the received sync signal. Other example RF generators, RF power delivery systems including one or more RF generators, and control methods for adjusting a state transition of a pulse to synchronize the state transition with a defined phase of a sync signal are also disclosed.