Motion and Focus Blur Removal from Pattern Images

摘要

A moving wafer imaging system processes wafer images to remove motion and focus blur by performing a blind deconvolution to determine an approximate point spread function. The approximate point spread function, estimated image noise and a Gaussian point spread function are used to compute a weighted point spread function. The weighted point spread function is used to filter out motion focus blur. Noise is then removed with a low-pass filter.

主权项

1. A semiconductor wafer inspection method comprising:
performing an image capture of a moving wafer with a wafer imaging device; calculating, with a processor, a weighted point spread function based on one or more of an approximate point spread function, a Gaussian point spread function, and an estimated image noise value; and performing, with the processor, a deconvolution on the image based on the weighted point spread function.