Patent ID: 7391510

Claim:
An inspection system operative to inspect patterned devices having microscopic conductors, the system comprising: at least first and second light sources, which illuminate a patterned substrate, said patterned substrate defining a substrate plane, wherein said first and second light sources define first and second paths of illumination, respectively; wherein said first and second paths of light are mutually non-parallel in a plane parallel to said substrate plane; a camera viewing a location of a candidate defect on said patterned substrate, and acquiring thereat at least one image of the location, said at least one image being illuminated by illumination from at least said first and second light sources; wherein said camera defines an optical axis and said first and second paths of illumination are offset from said optical axis; and wherein a response to illumination supplied along said first path of illumination is differentiable from a response to illumination supplied along said second path of illumination; and a defect classifier operative to receive said at least one image and to distinguish therewithin a candidate defect caused by a particle foreign to said patterned substrate from other types of candidate defects.