摘要 |
To reduce a stop time of transportation of wafers which occurs when one stepper handles many kinds of products, before exposure of semiconductor wafers of a first cassette port 7 a is completed, a process recipe for semiconductor wafers of a second cassette port 7 b is obtained from a host computer 2, the progress of the exposure of the semiconductor wafers of the first cassette port 7 a is detected via a sequencer 5, it is determined, based on the obtained process recipe, whether or not the semiconductor wafers of the second cassette port 7 b can be transported to an exposure stage following the last semiconductor wafer of the first cassette port 7 a, and a stepper 1 is caused to perform exposure in accordance with the determination result and the progress detection result. |