Abstract

The wide-band-gap GaN and Al_xGa_1−xN semiconductor system is the subject of much current interest for both its fundamental physical properties and for the potential applications of visible/near-UV optoelectronic devices.¹ Here we report the study of nonlinear optical effects and waveguide modes of these wide-band-gap and band-gap tunable semiconductor GaN and Al_xGa_1−xN epitaxial films. Low-pressure metalorganic vapor deposition (MGCVD) was used to grow epitaxial GaN and AlGaN layers on (0001) sapphire substrate. The absorbance spectra of a GaN film (with thickness 2.1 μm) is shown in Fig. 1. The x-ray diffraction showed the single crystalline structure of the epitaxial films.

© 1996 Optical Society of America