Defect inspection device and defect inspection method

Abstract

A defect inspection device is provided including: a stage on which a sample is to be placed and moved; an illumination optical system configured to irradiate the sample with illumination light; a detection optical system configured to detect scattered light generated at the sample by forming an image of the scattered light on an image sensor; a control device configured to control the stage; and a signal processing device configured to process a signal output from the image sensor. The signal processing device stores detection signals obtained by scanning a predetermined region of interest on a surface of the sample a plurality of times along a scanning trajectory that has a shift amount of a non-integer multiple of a pixel pitch of the image sensor, estimates intensity distributions of the detection signals of the object in the region of interest in a plurality of scans, detects a shift amount of the scanning trajectory based on the intensity distributions, and aligns and synthesizes the intensity distributions in the plurality of scans based on the detected shift amount, and acquires a point spread function related to the object in a sub-pixel unit having a data interval smaller than the pixel pitch.

Dependencies are inferred from the claim text.