Patent ID: 6059986
Filing Date: 2000-05-09
Classification: H01L

Abstract:
A method of monitoring a quartz heater in a wet station apparatus used for cleaning and wet etching a semiconductor wafer, the method comprising the steps of:measuring a temperature of a chemical solution;comparing the temperature measured with a predetermined reference temperature value, and outputting the result as a control signal;heating said chemical solution with a quartz heater;receiving the control signal output from a temperature control means, and analyzing the control signal to selectively output one of a first signal for increasing the power supplied to said quartz heater and a second signal for decreasing the power supplied to said quartz heater;receiving a heating process initiation signal, by a power switch connected to a power supply control means, for switching power to said quartz heater in response thereto; andconverting a current flowing into said quartz heater to a voltage signal using a current-to-voltage converter installed between said quartz heater and the power switch;comparing the voltage signal input from said current-to-voltage converter with a reference value, and outputting one of a third signal if the amount of current flowing into said quartz heater is lower than said reference value and a fourth signal if the amount of current flowing into said quartz heater is higher than said reference value; andmonitoring and analyzing operating states of said quartz heater and said power supply control means, respectively, and notifying a user of abnormalities in said respective operating states.