Patent ID: 8072591
Filing Date: 2011-12-06
Classification: G01N,H01L

Abstract:
1. An inspection system comprising: optics; an object support for mounting an object in a region of an object plane of the optics; a dark-field illumination light source; and an image detector having a radiation sensitive substrate disposed in a region of an image plane of the optics; wherein the optics provide an imaging beam path and a dark-field illumination beam path and comprise an objective lens, and a projection lens arranged wherein an orientation of chief rays of the illumination beam path varies across an object field imaged onto the radiation sensitive substrate by less than 5°; wherein an orientation of chief rays of the imaging beam path varies across the object field by less than 5°; wherein a numerical aperture of the imaging beam path on a side of the object plane is less than 0.1; wherein a numerical aperture of the illumination beam path on a side of the object plane is less than 0.1; and wherein at least one of the following relations is fulfilled: