The invention describes a method of frequency tuning an electrical generator (100) for supplying electrical power to a plasma, wherein the method comprises a pulsed mode, the pulse mode comprising at least a high power pulse (314) comprising a high power level (304) and a low power pulse (312) comprising a low power level (302) different to zero power, the method comprising the steps of: —providing RF-power with a high power starting frequency set comprising at least one high power starting frequency (502, 504, 506) at the high power pulse (314) with a predefmed high power pulse shape; —providing RF-power with a low power starting frequency set comprising at least one low power starting frequency (512, 514) at the low power pulse (312) with a predefmed low power pulse shape; —determining a reflected high power at the high power starting frequency (502, 504, 506); —tuning the high power starting frequency (502, 504, 506) to a different first high power frequency if the reflected high power exceeds a high power threshold value such that the reflected high power decreases below the high power threshold value; —determining a reflected low power at the low power starting frequency (512, 514); —tuning the low power starting frequency (512, 514) to a different first low power frequency if the reflected low power exceeds a low power threshold value such that the reflected low power decreases below the low power threshold value. The invention further describes a corresponding electrical generator (100), plasma processing system and computer program product. The method, the electrical generator, the plasma processing system and the computer program product may have the advantage that the stability of the plasma with respect to repeated and essentially identical high and low power pulses is used to reduce the controlling effort and to check the stability of the plasma process.

A plasma processing apparatus can control a ratio between an input power during a pulse-on period and an input power during a pulse-off period by a matching operation of a matching device provided on a high frequency transmission line for supplying the high frequency power as a continuous wave without a power modulation. An impedance sensor 96A provided in a matching device of a plasma generation system includes a RF voltage detector 100; a voltage-detection-signal generating circuit 102; an arithmetic-average-value calculating circuit 104; a weighted-average-value calculating circuit 106; and a moving-average-value calculating unit 108 of a voltage sensor system, and also includes a RF electric current detector 110; an electric current-detection-signal generating circuit 112; an arithmetic-average-value calculating circuit 114; a weighted-average-value calculating circuit 116; a moving-average-value calculating unit 118; and an impedance calculating circuit 120 of an electric current sensor system.

Provided are methods and apparatuses for smoothly transitioning from a first plasma condition to a second plasma condition in a plasma processing chamber. An apparatus for plasma processing may be equipped with an RF power supply coupled to an impedance matching network to smoothly switch from a continuous wave (CW) plasma to a pulsing plasma, reversely, or in alternation without quenching the plasma. Or, the plasma processing chamber may be equipped to smoothly switch from a pulsing plasma at a first duty cycle to a pulsing mode at a second duty cycle without quenching the plasma. Such transitions may occur by ramping RF power, ramping duty cycle, and/or ramping pulsing frequency of the RF power supply being delivered to the plasma processing chamber so that impedance can be smoothly changed and matched by the impedance matching network during the transitions.

A RF detector is provided and includes LO and RF paths, a mixer and a filter. The LO path includes a first buffer and a sine-to-square wave converter. The first buffer receives a first RF signal that is based on a RF input signal received by the RF detector. The RF input signal is detected within a substrate processing system. The sine-to-square wave converter converts a sine wave of the first RF signal to a square wave and outputs a LO signal having the square wave. The RF path includes a second buffer that receives a second RF signal and outputs a RF output signal. The second RF signal is based on the RF input signal. The mixer generates an IF signal based on the LO and RF output signals. The filter filters the IF signal to generate a DC signal, which is representative of the second RF signal.

Disclosed embodiments apply electron beams to substrates for microelectronic workpieces to improve plasma etch and deposition processes. The electron beams are generated and directed to substrate surfaces using DC (direct current) biasing, RF (radio frequency) plasma sources, and/or other electron beam generation and control techniques. For certain embodiments, DC-biased RF plasma sources, such as DC superposition (DCS) or hybrid DC-RF sources, are used to provide controllable electron beams on surfaces opposite a DC-biased electrode. For certain further embodiments, the DC-biased electrode is pulsed. Further, electron beams can also be generated through electron beam extraction from external and/or non-ambipolar sources. The disclosed techniques can also be used with additional electron beam sources and/or additional etch or deposition processes.

Systems and methods for adjusting power and frequency based on three or more states are described. One of the methods includes receiving a pulsed signal having multiple states. The pulsed signal is received by multiple radio frequency (RF) generators. When the pulsed signal having a first state is received, an RF signal having a pre-set power level is generated by a first RF generator and an RF signal having a pre-set power level is generated by a second RF generator. Moreover, when the pulsed signal having a second state is received, RF signals having pre-set power levels are generated by the first and second RF generators. Furthermore, when the pulsed signal having a third state is received, RF signals having pre-set power levels are generated by the first and second RF generators.

A process of forming a first mask on a first region of a metal film formed on a surface of a substrate, a process of modulating a work function of a first exposed region of the metal film, using plasma of a first process gas, a process of removing the first mask, a process of forming a second mask on a second region of the metal film, and a process of modulating the work function of a second exposed region of the metal film, using plasma of a second process gas are executed.

A radio-frequency (RF) generator is provided that includes an exciter, a power amplifier, a filter, a sensor, and a frequency-tuning subsystem. The frequency-tuning subsystem includes a non-transitory, tangible, machine-readable medium containing instructions to perform a method that includes receiving an impedance trajectory of the plasma load; receiving a reference point in a complex-reflection-coefficient plane, the reference point lying on a reference vector passing through the reference point and the origin; receiving, from the sensor, a measured impedance of the plasma load; determining a measurement angle between a reference vector and a line passing through the reference point and a point in the complex-reflection-coefficient plane corresponding to the measured impedance; scaling the measurement angle by a predetermined constant to produce a frequency step; adding the frequency step to the initial frequency to produce an adjusted frequency; and causing the exciter to generate a signal oscillating at the adjusted frequency.

A plasma generating device that improves plasma generating efficiency can further accommodate changes in plasma generating state because of changes in conditions of surroundings and the like. The plasma generating device is provided with an electromagnetic wave radiating device, which has an electromagnetic wave generating device that oscillates electromagnetic waves and a radiating antenna that radiates electromagnetic waves oscillated by the electromagnetic wave generating device, and a control device that controls the electromagnetic wave radiating device. The electromagnetic wave radiating device is provided with a power detector that detects traveling wave power output by the electromagnetic wave generating device and reflected wave power reflected from the radiating antenna, and the control device automatically controls the oscillation pattern for the electromagnetic waves on the basis of the proportion of the value for the reflected wave power to the value for the traveling wave power detected by the power detector.

A voltage sensor for a voltage controlled interface of a plasma processing system. The voltage sensor receives a RF signal generated by a pickup device. The RF signal is indicative of a RF voltage provided at a substrate in a plasma chamber. The voltage sensor includes first and second dividers corresponding to first and second channels and having first and second capacitance ratios. The dividers receive the RF signal and respectively generate first and second reduced voltage signals. A first output of the first channel outputs a first output signal based on the first reduced voltage signal and while the RF signal is in a first voltage range. A second output of the second channel outputs a second output signal based on the second reduced voltage signal and while the RF signal is in a second voltage range.