Tokyo Electron Limited

Kaori Arai

Toshihiko Iijima

Kazuhito Ogino

Disclosed is a method for appointing an orientation flat, in which when there are a plurality of orientation flats with the same length, any one from among the orientation flats of the same length can be certainly appointed as a reference orientation flat. In the disclosed method, three orientation flats at three positions are detected, respectively, through the rotation of a semiconductor wafer, the lengths of three circular arcs between the three orientation flats are obtained, respectively, and then an orientation flat at the right side of the longest circular arc from among the three circular arcs is appointed as a reference orientation flat. Accordingly, it is possible to certainly appoint a reference orientation flat even though there exist a plurality of circular arcs with the same length.

Method for appointing orientation flat, apparatus for detecting orientation flat, and program for appointing orientation flat

Disclosed is a pre-alignment method and a computer-readable medium storing a pre-alignment program capable of reducing pre-alignment time and transfer time of a semiconductor wafer. The pre-alignment method includes steps of rotating the semiconductor wafer transferred from a receiving unit onto a rotating body of a pre-alignment mechanism by a transfer mechanism, calculating and storing an eccentric value between a shaft center of the rotating body and a center of the semiconductor wafer detected by a sensor of the pre-alignment mechanism, correcting a positional deviation of the semiconductor wafer on the rotating body by the transfer mechanism according to the calculated eccentric value, when the calculated eccentric value exceeds a predetermined value, and estimating the eccentric value when conducting the pre-alignment operation for a succeeding semiconductor wafer, based on the eccentric value accumulated during the pre-alignment operation conducted for semiconductor wafers prior to the succeeding semiconductor wafer.

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Nirasaki, Japan

Kaori Arai