Patent ID: 6479832
Filing Date: 2002-11-12
Classification: G03F

Abstract:
A surface position detection apparatus for detecting a surface position of a substrate, the apparatus comprising:an illumination device that emits detection light along a light path toward a substrate surface from an oblique direction with respect to the substrate surface; an optical shaper disposed in the light path downstream from the illumination device, the optical shaper shaping the detection light into a slit-like shape to generate a slit-like light beam; an alteration device communicating with the optical shaper and altering only a width of the slit-like light beam by controlling the optical shaper; an optical element disposed in the light path downstream from the optical shaper, the optical element guiding the slit-like light beam onto the substrate surface; and a detector disposed in the light path and receiving the slit-like light beam reflected from the substrate surface.