Apparatus for measuring film thickness formed on object, apparatus and method of measuring spectral reflectance of object, and apparatus and method of inspecting foreign material on object

Abstract

A film thickness measurement apparatus () comprises an ellipsometer () for acquiring a polarization state of a film on a substrate () and a light interference unit () for acquiring spectral intensity of the film on the substrate (). In an optical system () of the light interference unit (), a light shielding pattern () is disposed in an aperture stop part (), and an illumination light from a light source () is emitted to the substrate () through the optical system (). A reflected light from the substrate () is guided to a light shielding pattern imaging part (), where an image of the light shielding pattern () is acquired. When the ellipsometer () performs a film thickness measurement, a tilt angle of the substrate () is obtained on the basis of the image of the light shielding pattern () and a light receiving unit () acquires a polarization state of the reflected light. An calculation part () obtains a thickness of a film with high precision from the polarization state of the reflected light by using the obtained tilt angle.