| Summary: | 碩士 === 元智大學 === 工業工程與管理學系 === 92 === Because of high type I error rate resulted by using an optical inspection machine for a local wafer manufacturing company, the inspection successful rate is only about 50%. The focus of this research is to develop an inspection software that will significantly reduce the type I error rate and thus reduce the loading of the human operators.
The developed inspection method consists of firstly using the gamma correction method to enhance wafer images and to filter out the brighter background regions. Secondly, after abstracting the R、G、B bands information, the maximum between-group binary thresholding method was applied individually, and then the three enhanced information were combined through a set of logic operations on their binary images. Finally the noise of the image was reduced by applying an of iterative median filter.
Total of 232 samples were tested using the developed methodology. Among them, the operators identified 132 normal and 100 defect images. The results of using the developed method would results in 24 samples (18%) to produce type I error; and 7 samples (7%) to produce type II error. However, the whole inspection successful rate is from original 50% increased to 87%. The inspection time is above 0.75 to 0.83 seconds.
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