Abstract: A cassette of conventional form is loaded with a plurality of semiconductor wafers having indexing flats of the known type and placed over three parallel rollers rotatably secured to a frame. The three rollers include a center roller and two side rollers positioned only slightly higher than the center roller such that their rotary motions can be communicated to the wafers by contact, depending on the position of the individual indexing flats. The indexing flats are roughly aligned in downward directions first by rotating only the center roller and after all three rollers are rotated to bring the indexing flats in upward directions, the wafers are more accurately aligned in a downward direction by rotating only the center roller and all three rollers are rotated thereafter for a predetermined period of time, depending on the desired angular position of the indexing flats.