Patent attributes
Provided is a capacitively coupled plasma processing apparatus which improves a controllability of the RF bias function and reliably prevents unwanted resonance from being generated on a RF transmission line between a counter electrode and ground potential to enhance reliability of the plasma process. In the capacitive coupled type plasma processing apparatus, three kinds of RF powers from a first, second and third RF power supplies (35, 36, 38) are superimposed and applied to susceptor (lower electrode) (16). In such a three-frequency superimposing and applying application scheme, the frequency-impedance characteristic around upper electrode (48) is considered to prevent a serial resonance from occurring on an RF transmission line around upper electrode (48) in consideration of all the low order frequencies of the IMD relevant to and affecting the plasma process. Since the fluorocarbon layer by itself functions as an antireflective film and a harm mask, the reliability of processing can be improved, while reducing the cost.