ROTATIONAL MISALIGNMENT MEASURING DEVICE OF BONDED SUBSTRATE, ROTATIONAL MISALIGNMENT MEASURING METHOD OF BONDED SUBSTRATE, AND METHOD OF MANUFACTURING BONDED SUBSTRATE

摘要

A rotational misalignment between semiconductor wafers constituting a bonded wafer is calculated. A light source is arranged at a position which is on a front side of an opening of a notch and which is separated from an outer edge portion of a bonded wafer by a predetermined interval, and outputs light to irradiate the outer edge portion of the bonded wafer including the notch. A camera receives and photoelectrically converts reflected light that is specularly-reflected by the outer edge portion of the bonded wafer including the notch among the light outputted by the light source in order to output a brightness distribution of the reflected light as an image. A computer analyzes positions of notches from the image outputted by the camera to obtain a notch position misalignment, and further calculates a rotational misalignment between semiconductor wafers using a center position misalignment between the semiconductor wafers.