High-frequency power supply device and reflected wave power control method

Abstract

In an RF power supply for supplying RF power to a plasma load, reflected wave power control is performed in which the reflected wave power of an RF generator is detected and the RF generator is controlled. For a short-time variation in reflected wave power, control is performed based on a peak value variation in the detection value of reflected wave power. For a long-time variation in reflected wave power, control is performed based on a variation in a smoothed value obtained by smoothing detection values of reflected wave power. A reflected wave power control loop system includes a reflected wave power peak value dropping loop system and an arc blocking system that perform control based on a peak variation in reflected wave power and a reflected wave power amount dropping loop system that performs control based on a smoothed power amount of reflected wave power.