APPARATUS FOR BLOCKING WILD CURRENT IN A FLOW CONTROL SYSTEM

摘要

The device for maintaining the amount of gas flow in a vacuum chamber, controls gas flows in layers entering the chamber to remove turbulence and contamination of wafers. The device having a flow control valve (3) connected with passage (30A), a flow detecting section (1), an output pneumatic valve (8) actuated by control signals from pneumatic valve, a comparing section (2) for opening/closing the valve (3) by detecting signal of the section (1), comprises input pneumatic valve (6) connected with gas input/output passages (30F,30A) and a controlling section (7) for controlling the valve (6), the section (2), the valve (8).