Patent ID: 9575010
Date: 2017-02-21
CPC Classifications: G01N,G03F

Claim:
1. An inspection apparatus comprising: a table configured to support an inspection object; a position measuring unit configured to measure a position coordinate of the table; a light source configured to emit light for illuminating the inspection object; an illuminating optical unit, wherein the illuminating optical unit includes: a transmissive illuminating optical unit configured to illuminate the inspection object with the light emitted from the light source, wherein the light is transmitted through the inspection object; a reflective illuminating optical unit configured to illuminate the inspection object with the light emitted from the light source, wherein the light is reflected by the inspection object; a first sensor, wherein the light transmitted through the inspection object by the transmissive illuminating optical unit, is incident thereto, configured to convert an optical image of the inspection object to an electric signal; a second sensor, wherein the light reflected by the inspection object by the reflective illuminating optical unit, is incident thereto, configured to convert an optical image of the inspection object to an electric signal; a comparing unit configured to detect a defect of a pattern of the inspection object by comparing optical image data output from at least one of the first sensor and the second sensor with reference image data generated from design data of the pattern, corresponding to the optical image data; a line width error obtaining unit configured to obtain a line width error by comparing a line width obtained from design data of the pattern and a line width of the pattern obtained from the optical image data; and a polarized beam splitter configured to be movable between the inspection object and the first sensor, and between the inspection object and the second sensor, wherein in the case where the polarized beam splitter is disposed along the light path of the light for illuminating the inspection object with the light to be transmitted, the polarized beam splitter is also disposed along the light path for illuminating the inspection object with the light to be reflected.