| 摘要 |
PURPOSE:To uniformize the angles of incidence on and reflection from a body to be inspected and to perform thin-film inspection with high accuracy by generating light emitted by a light source to uniform intensity, and converging and guiding only the parallel component of the reflected light from the body to be inspected. CONSTITUTION:The light emitted by the light source 10 is diffused uniformly by a diffusion plate 13 and reflected by a half-mirror 14 to illuminate the surface of a wafer 1 vertically. The reflected light from the wafer 1 passes through a mirror 14 and only parallel light on the wafer 1 is converged by a condenser lens 15. Then only single-wavelength light is selected through an interference filter 16 and electrode into an image pickup device 17. Then the light intensity is detected as to respective parts of the wafer 1 from the picked-up image data to measure the thickness, etc., of a film. Thus, the angle of the light incident on the wafer 1 is equal at the respective parts and the light propagation distance in the thin film becomes equal, so the same interference conditions are set at the respective parts. A thin film of resist formed on the wafer 1 is inspected with high accuracy. |
