Research on Real-time Image Stitching for Wafer Defect Inspection

Recently, with the development of the 4th industrial revolution technology, the importance and demand for memory semiconductors have increased rapidly, and the semiconductor market is expected to continue to expand in the future. One of the important processes in the semiconductor industry is wafer production, and since wafer yield is directly related to a company's competitiveness, improving wafer yield is a very important issue. Therefore, it is important to accurately detect and analyze wafer defects during semiconductor production. A predictive system is used to determine the cause of defects, in which vision camera and scope equipment is used. The prediction system currently in use perform manually when combining multiple photographic images into one image, which increases the time required to analyze defects and has the potential to result in production disruption. In this paper, we discuss an algorithm that automatically combining multiple photographic images and a method of implementing it with FPGA for real-time processing.