| 摘要 |
This invention intends to enable it to easily determine that the wafer has come to a predetermined measurement position so that a measurement command is issued to a sensor controller to start measurement. A wafer pre-alignment apparatus according to this invention includes a wafer rotating member ( 2 ), a rotation detecting member ( 3 ), a light emitting member ( 9 ) for emitting light toward the periphery of the wafer, a CCD linear sensor ( 26 ) linearly arranged and signal processing member for detecting the edge position of the wafer to acquire at least one of an orientation flat position, notch position and center position of the wafer on the basis of the edge position detected, and further includes an up-down counter ( 21 a) for converting a signal received from the rotation detecting member into rotating position information, a measured angle setting register ( 21 b) for storing the rotation position information when the wafer rotating member rotates by an interval angle and a comparator ( 21 c) for comparing a set value in the measured angle setting register and a counted value in the up-down counter.
|
