| 摘要 |
A suck back valve is proposed in which the response speed of a diaphragm is improved and in which control becomes assured, wherein there is no concern of changes occurring in an amount of sucked fluid, and wherein a system employing the suck back valve is kept small in scale, thereby enabling ease of installation. When a coating liquid is supplied to a fluid passage (60) from a coating liquid supply source (180), coating liquid drips from a nozzle (184) onto a semiconductor wafer (182). An ON/OFF valve (66) is activated, whereby an ON/OFF valve diaphragm (68) is displaced in the direction of arrow A, and supply of coating liquid is halted. In addition, when a linear voice coil type displacement device (148) is activated, a diaphragm (128) is displaced in the direction of arrow B, and coating liquid inside the fluid passage (62) becomes sucked thereby, so that any coating liquid inside the nozzle (184) is returned in the direction of arrow D. <IMAGE> |
