Patent ID: 7883600

Claim:
An RF supply system to be connected to an RF electrode, which is disposed through an insulating member outside or inside a process chamber comprising a conductive part connected to ground potential through a grounding path, to assist a plasma process performed in the process chamber, the system comprising: an RF power supply configured to supply an RF power for plasma generation to the electrode through a transmission path; a matching unit disposed on the transmission path between the RF power supply and the RF electrode and connected to the RF power supply through a first portion of the transmission path, the matching unit being configured to match an impedance as viewed from the RF power supply to the RF electrode, with an impedance of the RF power supply side; and an impedance converter disposed adjacent to or integrated with the RF electrode and on the transmission path between the matching unit and the RF electrode and connected to the matching unit through a second portion of the transmission path, the impedance converter comprising a first reactance element provided on the transmission path between the matching unit and the RF electrode in series therewith and a second reactance element connecting the transmission path to the grounding path in parallel with the process chamber, and the impedance converter being configured to set a load impedance on the RF electrode side, as viewed from the matching unit, to an impedance higher than an actual impedance on the RF electrode side, wherein the impedance converter is configured as a matching circuit network to match the actual impedance on the RF electrode side with a characteristic impedance of a transmission line which forms the second portion of the transmission path.