Patent ID: 8284395
Filing Date: 2012-10-09
Classification: G01N,H01L

Abstract:
1. A wafer surface measuring apparatus which measures a surface of the wafer by irradiating a laser beam on a wafer comprising: a measuring stage that supports an outer edge of the wafer and loads the wafer in a manner not contacting with a rear surface of the wafer and a stage surface; a wafer carrying means that moves the wafer over the measuring stage and loads the wafer on the measuring stage from an upward side; a rotary drive unit which rotates the measuring stage; and an ejection hole formed at a center portion of the stage surface to supply gas to a rear surface of the wafer loaded on the measuring stage, wherein the wafer carrying means includes a chuck which sucks and holds the surface of the wafer in a non-contact manner and bends the wafer in an upwardly convex shape.