VACUUM TREATMENT DEVICE WITH EXHAUST VALVE CONTROLLER

摘要

PURPOSE:To prevent a residual gas in an auxiliary chamber from flowing back into a vacuum treatment chamber by a method wherein the absolute pressures on the vacuum treatment chamber side and on the exhaust system side of a main exhaust valve for a vacuum treatment device are detected and the main exhaust valve is controlled accoding to the detection results. CONSTITUTION:In a vacuum treatment device having the auxiliary chamber 3 and the vacuum treatment chamber 1 connected to each other through an airtight gate 6, the first vacuum gage 16 and the second vacuum gage 17 are provided for respectively detecting the absolute pressure on the vacuum treatment chamber 1 side and that on the exhaust system side of the main exhaust valve 14. When the reading of the second vacuum gage 17 becomes lower than the first one 16 after the auxiliary chamber 3 is evacuated, the main exhaust valve 14 is opened in a controlled manner. By controlling the valve 14 in this manner, the residual gas in the auxiliary chamber 3 can be prevented from flowing back into the vacuum treatment chamber 1 thereby to contaminate the atmosphere in the latter.