METHOD FOR WATCHING THE CHEMICAL LIQUID DESPENSING STATE

摘要

PURPOSE: A method for watching a chemical liquid dispensing state is provided to monitor medicinal fluid coating from a nozzle tip by determining the state of dispensing of the nozzle tip based on the detection wave. CONSTITUTION: A light emitting sensor(131) generates the light passing through a lower part of a nozzle tip discharging medicinal fluid. A light receiving sensor(132) lights receive the light generated from the light emitting sensor. A sensor unit(130) detects the end part state of the Nozzle tip. A nozzle head having the nozzle tip is mounted on a holder included at the end part of an arm. The sensor is descended so that the light emitting sensor and light receiving sensor at both side of the nozzle heed are faced with each other. The descended sensor unit is horizontally moved from the edge to the center of a wafer. The certain volume medicinal fluid is sprayed from the nozzle tip on the wafer.