Non-contact measurement for 3D profile of hybrid metal thin film by white-light interference system

Abstract

We presented a novel optical non-contact measurement system for detection of the thickness and 3D profile of a hybrid film. The optical interference system and the corresponding compiled data processing program for realizing the non-contact detection of thickness and 3D profile of the hybrid metal film were designed. White light source was used to generate the optical interference of the hybrid Au-Ag metallic film. The characteristics of the film were analyzed through the interference fringe. The original color fringe is obtained from a CCD camera, and the Red-Green-Blue (RGB) raw fringe image is put into our compiled numerical program. The fringe phase was wrapped using Fourier transform technique. The unwrapped phase was reconstructed to be the whole-filed Z image and 3D profile by use of a bilateral filter.