FILM INSPECTION DEVICE AND METHOD

PROBLEM TO BE SOLVED: To quickly determine a crystal condition using a technique of ellipsometry.SOLUTION: While a sample on the surface of which a polycrystalline silicon thin film is formed is continuously moving in one direction, illumination light is radiated to the sample to separate reflection light from the sample to which the illumination light is radiated, into an s polarization component and a p polarization component. One part of the separated s polarization is changed in a polarization condition to generate p polarization. The p polarization generated by changing the polarization condition and one part of the p polarization separated from the reflection light are synthesized to generate synthetic light. The generated synthetic light is detected to obtain a first signal, and the p polarization remaining after removing one part of the p polarization separated from the reflection light is detected to obtain a second signal. A condition of crystal of the polycrystalline silicon thin film formed on the surface of the sample is determined on the basis of information obtained by processing the first signal and the second signal.