Short-Time Discrete Wavelet Transform for wafer microcrack detection

This paper presents design and proof-of-principle experiments for a real-time in-line wafer microcrack detection system. The line-scanning method is chosen because entire wafer can be inspected without image processing technology. Short-Time Discrete Wavelet Transform (STDWT) is developed in order to determine reflective characteristics of microcrack, and smaller computation complexity in order to shorten system resolving time.