Patent ID: 8411264
Filing Date: 2013-04-02
Classification: G01N

Abstract:
1. An apparatus for inspecting a substrate surface, the apparatus comprising: illumination optics for irradiating the substrate surface linearly with rectilinearly polarized light from an oblique direction; detection optics for acquiring images based on beams of light scattered from the substrate surface irradiated with the polarized light; and means for comparing an image selected as an inspection image from the plurality of substrate surface images that the detection optics has acquired, and another image selected from the plurality of substrate surface images as a reference image different from the inspection image to detect a defect; wherein the illumination optics includes polarization control means for controlling a polarizing direction of the light according to a direction orthogonal to a lengthwise direction of patterns of the substrate, and the polarization control means inclines the polarized light a angle to an orthogonal direction to a incidence plane of the polarized light, in which where α is azimuth angle at which rectilinearly polarized light enters, φ is rotation angle in x-y plane and θ is elevation angle; and wherein the illumination optics is constructed to irradiate the substrate at an azimuth angle inclined through 15° to 75° to the scanning direction of the substrate.