Patent ID: 7097784

Claim:
A method for etching semiconductor wafers in an etching apparatus including an etching bath filled with an etchant and capable of setting liquid temperature and process sequence, the method comprising: selecting a predetermined etching program suitable for etching of the semiconductor wafer; counting a number of the semiconductor wafers to be charged in the etching bath before the etching; calculating a temperature drop of the etchant based on the number of the semiconductor wafers; setting the liquid temperature of the etchant to an initial temperature B obtained by adding the temperature drop of the etchant to a predetermined etching temperature A, the predetermined etching temperature A being lower than the boiling point of the etchant; charging the semiconductor wafers in the etching bath after the liquid temperature reaches the initial temperature B to etch the semiconductor wafers; and setting the liquid temperature at the predetermined etching temperature A, immediately before or after charging the semiconductor wafers.