Patent ID: 7372560

Claim:
A pattern inspection apparatus to inspect pattern defects of a substrate in which a pattern is formed comprising: an illumination optics which applies a first inspection light of a predetermined wavelength to a surface opposite to a pattern formed surface of the substrate, and applies a second inspection light whose wavelength is equal to the predetermined wavelength of the first inspection light to the pattern formed surface; a detector which selectively detects a transmitted light through the substrate by irradiation of the first inspection light and a reflected light from the substrate by irradiation of the second inspection light so as to perform a transmitted light-based inspection and a reflected-light-based inspection; and a space separation mechanism which is provided in the vicinity of an optical focal plane toward the pattern formed surface of the substrate, and spatially separates an irradiation area of the first inspection light and the second inspection light such that the transmitted light through the substrate is imaged in one area on the optical focal plane separated from another area where the reflected light from the substrate is imaged.