| 摘要 |
<p>PROBLEM TO BE SOLVED: To accurately control a flow rate of a fluid which is sucked by a flexible member, by providing a suck back mechanism which sucks the fluid in a flow path under the negative pressure which is generated by displacement of the flexible member, and controlling an amount of displacement of the flexible member under driving operation of a motor-driven linear actuator. SOLUTION: When a signal is output to a flow controlling means 68, pressured fluid is fed to a cylinder room 48 of an on/off valve mechanism 26, and pilot pressure is controlled to a given value. The fluid shifts a piston 50 against a spring member 54, a diaphragm 56 separates from a seat part 59, and the valve mechanism 26 is turned on. Thus, coating liquid flows along a flow path 38 and drips onto a semiconductor wafer. By turning off the valve mechanism 26, driving a linear actuator 118 of a suck back mechanism 28, and returning the coating liquid to the suck back valve 20 side using negative pressure operation of a diaphragm 100 which is raised under operation of a spring member 98, liquid is prevented from dripping.</p> |
