| 摘要 |
PURPOSE:To control the pressure of the gas supplied between wafer electrodes to a fixed level by providing two buffer rooms and reducing the pressure level in two steps for the control of pressure. CONSTITUTION:The gas delivered from a gas cylinder 5 serving as a gas supply source and a pressure control valve 6 is led to the 2nd pressure control mechanism part consisting of a throttle valve 7, a pneumatic switch valve 12, a buffer room 13 and a diaphragm vacuum gauge 14 connected in series to each other via the 1st pressure control mechanism part consisting of a throttle valve 7, a pneumatic switch valve 8, a buffer room 9 and a vacuum switch 10. The pressure of the gas reduced through said two control mechanism parts is detected by the switch 10 and the gauge 14. A controller 17 controls both valves 8 and 12 by the output signal given from a meter relay 16 connected to the switch 10 and the gauge 14. Then the gas undergone with the pressure control is led between a wafer 4 and a lower electrode 2 within a vacuum container 1 via a pneumatic switch valve 18 which feeds and stops the gas. |
