Patent attributes
Apparatus for and a method of cleaning or processing a wafer anticipates a malfunction of a pump and avoids an abrupt shutting down of the pump during the cleaning or processing of the wafer. The apparatus includes a tank vessel containing a liquid used in the cleaning or processing of the wafer, a pump that pumps the liquid chemical from the vessel, a filter that filters impurities contained in the liquid pumped by the pump, a heater that heats the filtered liquid to a predetermined temperature and supplies the heated liquid back into the tank vessel, and a pump malfunction anticipation unit that operates at the same time as the pump. The pump malfunction anticipation unit calculates the flow rate of the liquid pumped by the pump using a program, and based on the flow rate anticipates when it is time to replace the pump.
