Apparatus for reading marks on a semiconductor substrate

摘要

An apparatus and a method for reading a mark on a wafer. The apparatus includes a wafer receptacle having a mirror material coated on one side and a plurality of slots formed therein. The wafer receptacle is coupled to a base plate via a back support. The apparatus may also include a front support coupled between the wafer receptacle and the base plate. A plurality of concave mirrors are coupled to the base plate. A wafer placed in one of the plurality of slots reflects light to the mirror material coating the wafer receptacle. The light is reflected by the mirror material to one of the concave mirrors, which rectifies an image contained in the light and reflects the rectified image to the back support. The image can be viewed on the back support.