HIGH-FREQUENCY POWER SUPPLY DEVICE AND REFLECTED WAVE POWER CONTROL METHOD

摘要

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, using the detected reflected wave power, 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. In the non-ignition state before plasma is ignited, the RF generator provides total reflected wave power tolerance that is the ability to tolerate total reflected wave power generated when forward wave power all returns to the generator side as reflected wave power.