Mitsubishi Denki Kabushiki Kaisha

Ayumu Onoyama

Koichi Sakurai

Hiroyuki Ishii

Tatsuya Fujii

Kazuhiro Oka

Katsuhiro Fujiyoshi

Transforming optical images of a portion including a normal conductor pattern having a surface roughness, a portion subjected to an inspection, and a reference portion to images of electric charges and picking up these as electric signals by an image pick-up device, rendering the optical image including the normal conductor pattern having the surface roughness to a pixel signal by the image pick-up device, controlling a light volume of the optical image so that the pixel signal is saturated or immediately before the saturation, picking up a pixel signal of the portion to be inspected under this light volume, obtaining a differential signal from a pixel signal picked up from the reference portion, and judging an existence of defect from the differential signal, so as to detect defects such as a hiatus of conductor, a short circuit, and a deposition of an extraneous matter on a wafer, on which the normal conductor pattern having the roughened surface, with a high accuracy in processes of forming films and etching in manufacturing a semiconductor device.

Defect inspection method and defect inspection equipment

A defect detection system to check any defect in the pattern to be checked by comparing a pattern to be checked with a reference pattern includes an edge detection means for detecting a pattern edge of the pattern to be checked by scanning a substrate by laser beams and detecting reflected light thereof. After the relative position between the substrate and the imaging means is adjusted so that the pattern edge of the pattern to be checked is substantially aligned with one side of CCD pixels, an image of the pattern to be checked is picked up. Therefore, the defect detection system corrects misalignment less than one pixel between a pattern to be checked and a reference pattern to prevent occurrence of a false defect.

Growing community of inventors

Tokyo, Japan

Ayumu Onoyama