Efficient chip counting system with a modified scanner

Abstract

A low-cost imaging system capable of recognizing and counting semiconductor good dice is designed and is proven experimentally to be effective. The system utilizes a commercial scanner with the least modification of its inner optics by a beamsplitter-insertion method. Patterns on specular die surfaces therefore can be grabbed clearly, which results in the marks on defective dice being distinguishable. Also, a mask algorithm is developed to count the good dice on an adhesive tape, according to the gray-level histogram and the converted binary picture of the scanned image. The built-in software associated with the scanner, which is reliable and user-friendly, can also be incorporated into the designated algorithm without paying an additional price for system development, (C) 1998 Society of Photo-Optical Instrumentation Engineers.