An impedance matching device includes: a variable capacitor in which a plurality of series circuits of capacitors and semiconductor switches are connected in parallel; a calculation unit that calculates an impedance or a reflection coefficient on the load side using information regarding impedance acquired from the outside; and a control unit that determines ON/OFF states to be taken by the semiconductor switches included in the variable capacitor using the impedance or the reflection coefficient calculated by the calculation unit and turns on or off the semiconductor switches based on the determined states. The control unit changes an ON/OFF control timing between one and another of the semiconductor switches.

An impedance adjusting circuit includes: a first node coupled to a resistor; a first impedance unit having an impedance value determined based on a first impedance code and coupled between a first voltage terminal and a second node; a first switching unit suitable for electrically connecting the first node and the second node to each other in response to a clock; a first average voltage unit suitable for generating an average voltage of the first node; a first comparison unit suitable for comparing the average voltage of the first node with a first reference voltage to produce a comparison result of the first comparison unit; and a first code generation unit suitable for generating the first impedance code in response to the comparison result of the first comparison unit.

An impedance adjusting circuit includes: a first node coupled to a resistor; a first impedance unit having an impedance value determined based on a first impedance code and coupled between a first voltage terminal and a second node; a first switching unit suitable for electrically connecting the first node and the second node to each other in response to a clock; a first average voltage unit suitable for generating an average voltage of the first node; a first comparison unit suitable for comparing the average voltage of the first node with a first reference voltage to produce a comparison result of the first comparison unit; and a first code generation unit suitable for generating the first impedance code in response to the comparison result of the first comparison unit.

A method and a device for matching an impedance of pulse radio frequency plasma, and a plasma processing device are provided. In the method, a matched frequency is searched for sequentially in high radio frequency power phases of an i-th pulse period and multiple pulse periods following the i-th pulse period, and a specific modulation frequency determined in a process of searching for the matched frequency in a previous pulse is assigned as an initial frequency for the subsequent pulse. In this way, it is equivalent to increasing a width of a first radio frequency power phase of a pulse period. Therefore, by sequentially performing frequency modulation in the first radio frequency power phases of the multiple pulses, a matched frequency of pulse radio frequency plasma of a high pulse frequency can be found, thereby achieving impedance matching of plasma of a high pulse frequency.

An RF source impedance is raised with an impedance step-up transformer and a matching circuit is coupled between the stepped up impedance RF source and a RF load wherein the RF load impedance can be matched to the stepped up RF source impedance with a matching network comprising a variable capacitor and a variable inductor having single match solutions for all frequencies and impedances so long as the RF load impedance is less that the stepped up RF source impedance. A RF attenuator may be used to provide a better impedance load to the RF source during match determination and adjustment of the variable capacitor and variable inductor. Automatic impedance matching measures the RF source frequency and RF load voltage, current and phase to determine a single match solution for a capacitive value of the variable capacitor and an inductive value for the variable inductor.

An RF source impedance is raised with an impedance step-up transformer and a matching circuit is coupled between the stepped up impedance RF source and a RF load wherein the RF load impedance can be matched to the stepped up RF source impedance with a matching network comprising a variable capacitor and a variable inductor having single match solutions for all frequencies and impedances so long as the RF load impedance is less that the stepped up RF source impedance. A RF attenuator may be used to provide a better impedance load to the RF source during match determination and adjustment of the variable capacitor and variable inductor. Automatic impedance matching measures the RF source frequency and RF load voltage, current and phase to determine a single match solution for a capacitive value of the variable capacitor and an inductive value for the variable inductor.

Automatic impedance matching measures the RF source frequency and RF load voltage, current and phase to determine a single match solution for a capacitive value of the variable capacitor and an inductive value for the variable inductor, and whether a shunt reactance is coupled to the RF source or RF load. Once the capacitance and inductance values for a match solution are determined they are contemporaneously selected without any iterative searching necessary for the match solution.

Automatic impedance matching measures the RF source frequency and RF load voltage, current and phase to determine a single match solution for a capacitive value of the variable capacitor and an inductive value for the variable inductor, and whether a shunt reactance is coupled to the RF source or RF load. Once the capacitance and inductance values for a match solution are determined they are contemporaneously selected without any iterative searching necessary for the match solution.

In one embodiment, an impedance matching network includes a mechanically variable capacitor (MVC), a second variable capacitor, and a control circuit. The control circuit carries out a first process of determining a second variable capacitor configuration for reducing a reflected power at the RF source output, and altering the second variable capacitor to the second variable capacitor configuration. The control circuit also carries out a second process of determining an RF source frequency, and, upon determining that the RF source frequency is outside, at a minimum, or at a maximum of a predetermined frequency range, determining a new MVC configuration to cause the RF source frequency, according to an RF source frequency tuning process, to be altered to be within or closer to the predetermined frequency range. The determination of the new MVC configuration is based on the RF source frequency and the predetermined frequency range.

In one embodiment, an impedance matching network includes a mechanically variable capacitor (MVC), a second variable capacitor, and a control circuit. The control circuit carries out a first process of determining a second variable capacitor configuration for reducing a reflected power at the RF source output, and altering the second variable capacitor to the second variable capacitor configuration. The control circuit also carries out a second process of determining an RF source frequency, and, upon determining that the RF source frequency is outside, at a minimum, or at a maximum of a predetermined frequency range, determining a new MVC configuration to cause the RF source frequency, according to an RF source frequency tuning process, to be altered to be within or closer to the predetermined frequency range. The determination of the new MVC configuration is based on the RF source frequency and the predetermined frequency range.