Positioning of Characteristic Points in IC Chip’s Micro-Topography Based on Cross Correlation Matching and Image Projection Transformation
Zhong Wei Liang, Chun Liang Zhang, Yi Jun Wang, Yi Dan Hu · Advanced materials research · 2010
In accurate optical inspection of IC chip, it is necessary to recognize and calibrate the IC micro-topography completely and accurately. Positioning method of characteristic points in IC chip’s micro-topography based on cross correlation matching and image projection transformation is investigated to realize high precision detection of surface topography. On the basis of extracting wavelet high-frequency components of IC topography conjugate images which is shot by high- definition CCD cameras from different space positions, the coordinate information of some selected topography’s characteristic points is shown. Cross correlation matching is applied to definite the characteristic point’s relative positions in the projected images, then relationship of image projection transformation is established for calculating and determining the characteristic point’s absolute coordinates, which facilitates following topography detection of IC chip. Experiment analysis and data comparison indicate that accurate coordinate positioning results of characteristic points can be obtained by this method, the research basis for following IC topography model structuring and micro- flaw characteristic detecting can also be provided.