Vacuum deposited biaxial thin films with all principal axes inclined to the substrate

We begin by considering the three effective principal refractive indices an d the effective axes of a periodic layered medium in which the component la yers are tilted- columnar biaxial films formed by vacuum deposition in diff erent planes. A parameter window within which the effective principal refra ctive indices are well separated and all three effective axes are inclined to the substrate is found for titanium oxide. Next, a set of parameters fro m the window is transported directly to the regime of bideposition, in whic h nanometer-scale subdeposits of the components are made serially as starti ng values for the automated growth of inclined biaxial media. Finally index values and angles are estimated for three samples, using an optimization t echnique in which experimental and computed angular phase retardance maps a re matched. (C) 1999 American Vacuum Society. [S0734-2101(99)01105-7].