Development of 3-D Surface Profiler for Film-covered Objects using Phase-Shifting Interferometry

Abstract

Based upon a previously proposed algorithm for a film-covered surface, we are developing a new surface profiler which enables simultaneous measurement of the surface profile and the film thickness using phase-shifting interferometry. We propose a practical technique to estimate the necessary system parameters and sample parameters, which uses a Si wafer sample covered with a tapered film. Some experimental results are presented for film-covered surfaces consisting of approximately 70nm SiO2 film on silicon substrate.