The present application belongs to the technical field of
semiconductor wafer detection, and particularly relates to a
wafer surface
topography defect detection
system based on three-dimensional
point cloud reconstruction, comprising: a division module that obtains three-dimensional
point cloud data of a
wafer to be measured and fits a
reference plane, selects the original point closest to the center of the
reference plane as an initial sampling point, and divides the data into N subsets and distributes them to
parallel computing units; a calculation module that iteratively performs farthest point sampling, takes the distance of the new point as a step size, combines a preset constant to update the Z-axis weight of the anisotropic
Euclidean distance, recalculates the distance in each unit and selects the locally farthest point, and obtains the globally farthest point; and an identification module that fits a reference polynomial surface based on the sampled
point set, calculates the orthogonal distance deviation of the three-dimensional
point cloud data of the entire wafer to be measured to the surface, determines an abnormal threshold value according to the deviation, and identifies
topography defects. The present application enhances the stability of the
system to outliers, and reduces the
false detection and missed detection rates of
topography defects.