Patent ID: 8107065
Filing Date: 2012-01-31
Classification: G01N

Abstract:
1. A method for detecting a defect, comprising the steps of: irradiating a slit shaped area on a specimen, on which circuit patterns including repetitive patterns are formed, with light which is formed to irradiate the slit shaped area from an oblique direction; detecting scattered light which is scattered to a side or back direction of the irradiation direction area on the specimen by blocking belt-shaped light scattered from the repetitive patterns, thereby obtaining a detection signal; and processing said detection signal to detect defects, including foreign matter, on the specimen; and displaying said detected defects on a display device; wherein the step of irradiating further comprises a step of setting an azimuth angle at which the specimen is irradiated with the light from said oblique direction to detect side or back scattered light during the step of detecting and to detect foreign matter which is smaller than a wavelength of the light during the step of processing.