Wafer inspection apparatus for semiconductor manufacture, generates correction signal based on deviation of rotation angle from reference angle

摘要

A measuring device (17) is provided for detecting the current rotation angle of a feeder (4) w.r.t. its axis of rotation (Z). A control device (21) generates a corrective setting signal from the deviation of the rotation angle from a reference angle, and outputs the setting signal to a drive unit (18). The drive unit includes a stepper motor (19) with high-resolution angle positioning.