Development of Defect Verification System of IC Lead Frame Surface using a Ring-lighting

Abstract

It is especially needed for the IC lead frames used in the manufacture of semiconductors, which require both high quality and miniaturization. To overcome above, automatic defect detection systems based on image processing methods were proposed. Especially, this paper focuses on methods using the surface normal direction to detect a deformation in flat parts. Since most of these methods use a fixed parameter, the risk of missing a defect in industrial parts becomes a problem. In this paper, new defect detection method is proposed for detecting various defect sizes and defect types. This method determines the appropriate block size based on the median value of luminance dispersions calculated for several block sizes and learning from a sample that detects a defect point beforehand. We used 105 samples in our experiments. Our experimental results show our proposed method selects the superior parameters and identification of the defect area selected is superior with learning in detecting defects of several sizes.