Fourth optical inspection of integrated circuits using image processing and mathematical morphology: a report

Abstract

As competition gets tighter in the industrial world, many manufacturers are switching from the classical labor intensive methods of production to more sophisticated techniques using automation. At the microprocessor division of Motorola Inc. this approach was taken in a systematic manner. An automation group was founded with the ultimate goal of automating the testing procedures of their product. This testing procedure consists of two major tasks. First an electrical test is performed on the microprocessors to insure that they meet the required electrical specifications. Second a visual inspection of the packages is undertaken to reject the parts with surface flows, such as bubbles, blisters, chips, cracks, and voids. The latter inspection will be of interest to us in this dissertation. The purpose of this work is to perform the visual inspection automatically. The method used is image processing. In particular mathematical morphology is viable because it is the study of shapes. As we will find in this report, defects are merely abnormal shapes of the packages.