OPTICAL-PROPERTIES OF CD1-XMGXTE EPITAXIAL LAYERS - A VARIABLE-ANGLE SPECTROSCOPIC ELLIPSOMETRY STUDY

The index of Cd1-xMgxTe ternary alloys was measured for the first time by variable-angle spectroscopic ellipsometry on layers of different c oncentrations. The ellipsometer's wide spectral range (0.7-5.6 eV) cle arly reveals critical points beyond the gap. Self-consistency of the p ermittivity measurements is investigated by Kramers-Kronig analysis. A transition layer is revealed at the top surface of the samples and is taken into account as a rough layer. In the transparent region Sellme ier's law is applied to describe the index behavior as a function of t he wavelength and the magnesium content. (C) 1995 American Institute o f Physics.