| 摘要 |
<P>PROBLEM TO BE SOLVED: To control a self-bias voltage with a simple structure. <P>SOLUTION: In a plasma processing, plasma is formed by an electric field and a magnetic field of microwaves and positive ions are entered onto a board by a plasma potential of the plasma. Further, a leakage current is flown from the board toward the ground through a board support mechanism for supporting the board in the plasma in a state that it is electrically floated, and the self-bias voltage of the board generated by the plasma potential is suppressed by a voltage drop by this leakage current. The control of the self-bias voltage by the voltage drop is carried out by setting a resistance between the board support mechanism and the ground. In setting the resistance, the self-bias voltage of the board is detected and the obtained voltage value is fed back to increase or decrease a magnitude of the resistance so that the self-bias voltage comes to a given value. <P>COPYRIGHT: (C)2009,JPO&INPIT |
