Abstract
The research is focused on the topic of template matching with microscopic image at wafer level by image processing methods. Due to the occurrence of defect in the wafer, the template and the sample wafer-level microscopic image might be different. Among existing template matching methods, key point feature matching methods match image position by local feature of multiple locations. Key point feature matching method define specific local structure as keypoint. Matching ambiguity occurs when most of the keypoint feature are similar. Against this disadvantage, we propose rotation-invariant feature matching method, which matches images independent of any specific local structure. Combined with speed-up image processing method and data structure analysis method, we reduce the computation time of building and matching image features. Our research tested rotation–invariant feature matching method with wafer-level microscopic image provided by TSMC which was tested and failed by using keypoint matching method. Our method can successfully match all images among them. The average computation time of image matching by our method is 28.24 second, with only 2.05 pixel average geometric error.