The Indices of Refraction of Molecular-Beam Epitaxy-Grown BexZn1-xTe Ternary Alloys
Authors: Peiris, F.C.; Buckley, M.R.; Maksimov, O.; Munoz, M.; Tamargo, M.C.
Source: Journal of Electronic Materials, Volume 32, Number 7, 1 July 2003 , pp. 742-746(5)
Abstract:We have used a combination of prism-coupling, reflectivity, and ellipsometric techniques to investigate the indices of refraction, n, of a series of BexZn1-xTe thin films grown on InP substrates. After determining the concentrations of each of the BexZn1-xTe alloys using x-ray diffraction measurements, we measured their n at discrete wavelengths using a prism-coupler setup. In addition, we used reflectivity measurements to complement the prism-coupler data and arrive at the dispersion relations of n for the BexZn1-xTe alloys below their fundamental energy gaps. We then employed a rotating analyzer-spectroscopic ellipsometer to measure the complex reflection ratio for each of the films at angles of incidence of 65°, 70°, and 75°. By using the n values obtained from both the prism-coupler and the reflection-spectroscopy techniques to guide the ellipsometric analysis, we were able to obtain accurate results for the dispersion of n for the BexZn1-xTe alloys, not only below their fundamental energy gaps, but also above their energy gaps (up to 6.5 eV) using these three complementary techniques.
Document Type: Research Article
Publication date: 1 July 2003