OPTICAL INVESTIGATIONS OF MIXED-PHASE BORON-NITRIDE THIN-FILMS BY INFRARED SPECTROSCOPIC ELLIPSOMETRY

We focus on the application of infrared spectroscopic ellipsometry (IR SE) to simultaneously determine phase and microstructure of mixed-phas e thin films such as polymorphic-polycrystalline boron nitride (BN) th in films deposited by magnetron sputtering on (100) silicon. We discus s a recently presented microstructure-dependent model for infrared opt ical properties of mixed-phase thin films which contain anisotropic ma terials. In particular, the IRSE data are sensitive to the pure or mix ed hexagonal (h) and cubic (c) BN thin film layer structure, phase com position and average grain c-axis distribution of the hexagonal phase. (C) 1998 Elsevier Science S.A.