PURPOSE: To prevent reduction in throughput by providing a process for exposing a pattern for identifying a wafer which can be visually read or can be read by a machine except patterns of a semiconductor element.

CONSTITUTION: A photo resist is applied to a semiconductor wafer 1, a semiconductor element pattern 2 is exposed by a reduction projection exposure device, and then a pattern for identifying a wafer 3 is exposed. In this case, if different patterns 2 an 3 are exposed by the reduction projection exposure device one by one, a drastic reduction in throughput is induced and thereby a unit for exposing the pattern for identification 3 is added to a device for performing development and the pattern for identification 3 is exposed during waiting period before development in the development sequence, thus preventing failure in the semiconductor device due to formation of a pattern, eliminating reduction in throughput, and reducing operation time of the reduction projection exposure device.