Patent ID: 7746461
Filing Date: 2010-06-29
Classification: G01N,H01L

Abstract:
1. An optical defect inspection apparatus comprising: a light illuminating unit for illuminating a light to an object to be inspected; a first light detecting unit of an optical system for detecting a light scattered from the inspected object; an inspected object moving unit for moving the inspected object such that a position on the inspected object illuminated by the light from the light illuminating unit is changed; an inspected object holding unit for holding the inspected object; and a focal position aligning unit for detecting the light illuminated from the light illuminating unit and reflected by the inspected object, obtaining height information of a surface of the inspected object, and aligning a focal position of the first light detecting unit of the optical system based on the obtained information, wherein the focal position is aligned by combined control of an operation of vertically moving the inspected object holding unit and an operation of spraying the gas toward the rear surface thereof.