Importance

Loading Importance Indicators...

Abstract

The method and apparatus for positioning a semiconductor wafer incorporates an X.Y axis drive mechanism for moving a mounting bed with a rotary part mounted on the mounting bed for supporting a wafer horizontally and rotating around the vertical axis. An edge portion distance measuring device optically measures a distance from the center position of the rotary part to the edge portion of the wafer along intervals of a definite angle. A distance and angle calculating device calculates a distance between the center position of the wafer and the rotational center of the rotary part relative to a reference line, and an angle of a line connecting the center position of the wafer and the rotational center of the rotary part with respect to the reference line. A notched portion calculating device calculates a deflection angle of the notched portion of the wafer with respect to the reference line, and a deflection amount calculating device calculates the X.Y deflection amount of the center position produced by moving the center position of the wafer based on the data of the angle and distance calculated by the distance and angle calculating device.

Loading the Abstract Image...

First Claim