Optical constants of Ga_xIn_1-xP lattice matched to GaAs

Authors

Mathias Schubert, University of Nebraska-LincolnFollow
V. Gottschalch, University of Leipzig
Craig M. Herzinger, University of Nebraska-Lincoln
Huade Yao, University of Nebraska-Lincoln
Paul G. Snyder, University of Nebraska-LincolnFollow
John A. Woollam, University of Nebraska-LincolnFollow

Date of this Version

4-1-1995

Comments

Published in J. Appl. Phys. 77 (7), 1 April 1995. Copyright 1995 American Institute of Physics. Used by permission.

Abstract

The optical constants of Ga_0.51In_0.49P have been determined from 0.8 to 5.0 eV using variable-angle spectroscopic ellipsometry measurements at room temperature. The metal-organic vapor-phase-epitaxy-grown samples were x-ray analyzed to confirm lattice matching to the GaAs substrate. The effects of the native oxide were numerically removed from the data to determine the intrinsic optical constants. This is important because the optical constants reported become generally useful for modeling multiple-layer structures. A Kramers-Kronig analysis was used to reduce interference-related fluctuations in the below-gap refractive index. Near the band edge a mathematical form for excitonic absorption was included. Critical point energies were extracted using a numerical second-derivative fitting algorithm.