Patent ID: 8217579

Claim:
A device for controlling a DC bias of a RF discharge system, characterized in that the device comprises a mode selection module, a DC bias detection module, a DC bias controlling module and a RF power providing module; said mode selection module is used for receiving input information including a parameter and a type of the parameter; judging the type of the parameter, and if the type of the parameter is representative of being related to power, outputting the parameter as a power-related representative parameter to the RF power providing module; if the type of the parameter is representative of being related to voltage, outputting the parameter as a voltage-related representative parameter to the DC bias controlling module; said DC bias detection module is used for detecting the DC bias of an electrode of the discharge system and outputting a detected DC bias value to the DC bias controlling module; said DC bias controlling module is used for receiving the voltage-related representative parameter from the mode selection module and the DC bias value from the DC bias detection module; calculating a power value according to a DC bias controlling algorithm by utilizing said DC bias value and said voltage-related representative parameter, and outputting the calculated power value to the RF power providing module; said RF power providing module is used for providing the electrode of the discharge system with power according to the power-related representative parameter upon receipt of the power-related representative parameter from the mode selection module; and providing the electrode of the discharge system with power according to the power value calculated by the DC bias controlling module upon receipt of the calculated power value.