Coating apparatus

Abstract

A coating apparatus includes an open/close valve having a motor that allows control of opening operation and closing operation in accordance with electric signals applied from a controller. The coating apparatus further includes a suck back valve having a motor that allows control of a volume variation in a flow path for suck back that is in communication with an upstream side and a downstream side of a pipe in accordance with electric signals. The controller allows control of start of the closing operation of the open/close valve and start of suction operation of the suck back valve through application of the electric signals to the motors, respectively. This achieves simple adjustment of liquid cut-off.

1 . A coating apparatus comprising:
 a nozzle dispensing chemical to a substrate;   a pipe in communication with the nozzle;   a chemical supplying unit supplying the chemical through the pipe to the nozzle;   an open/close valve on the pipe between the nozzle and the chemical supplying unit, and having an open/close drive unit that allows adjustment of opening operation and closing operation in accordance with electric signals, the open/close valve opening/closing the pipe;   a nozzle-side filter on the pipe between the nozzle and the open/close valve;   a suck back valve on the pipe between the nozzle-side filter and the open/close valve, and having a suction/push drive unit that allows adjustment of a volume variation in a flow path in communication with an upstream side and a downstream side of the pipe in accordance with electric signals; and   a controller applying the electric signals to the open/close drive unit and the suction/push drive unit for controlling start of the closing operation of the open/close valve and start of suction operation of the suck back valve.   
     
     
         2 . The coating apparatus according to  claim 1 , wherein
 the controller performs control through application of the electric signals to the suction/push drive unit so as for the volume variation in the flow path of the suck back valve to be larger than that with no nozzle-side filter.   
     
     
         3 . The coating apparatus according to  claim 1 , wherein
 the controller performs control through application of the electric signals to the suction/push drive unit so as to start the suction operation to increase a volume in the flow path of the suck back valve simultaneously with or before the start of the closing operation of the open/close valve.   
     
     
         4 . The coating apparatus according to  claim 1 , wherein
 the controller performs control through application of the electric signals to the suction/push drive unit so as to start the suction operation to increase a volume in the flow path of the suck back valve after the closing operation of the open/close valve is finished.   
     
     
         5 . The coating apparatus according to  claim 1 , further comprising:
 a joint joining the nozzle-side filter detachably to the pipe on the upstream side and the downstream side of the nozzle-side filter; and   a joint moving mechanism moving the joint so as for an opening of the joint on the downstream side of the nozzle-side filter to be higher in level than a front opening of the nozzle.