Patent ID: 6771481
Filing Date: 2004-08-03
Classification: H01J,Y10T

Abstract:
A plasma processing apparatus comprising:a body of the plasma processing apparatus including a vacuum processing chamber that contains a wafer stage on which a semiconductor wafer is held, a plasma producing unit for producing plasma within said vacuum chamber, and a high frequency source for applying a high frequency bias voltage to said wafer stage; and a control unit for controlling various parameters of said body of the plasma processing apparatus, wherein said control unit includes a detecting unit for detecting a high frequency voltage and high frequency current applied from said high frequency source to said wafer stage and for obtaining a phase difference between the high frequency voltage and the high frequency current applied to said wafer stage, wherein said detecting unit further detects, at an output of an equivalent circuit of said wafer stage, a voltage generated at said wafer and a current flowing into said wafer, and a phase difference between said voltage generated at said wafer and said current flowing into said wafer.