The invention concerns an apparatus for inspection of a wafer, encompassing at least one incident-light illumination device that radiates an illuminating light beam which is incident obliquely onto a surface of a wafer to be inspected, and an image capture device for capturing an image of the surface...http://www.google.com/patents/US7248354?utm_source=gb-gplus-sharePatent US7248354 - Apparatus for inspection of a wafer
