Structure of GaAsN alloy within miscibility gap
Journal
2016 5th International Symposium on Next-Generation Electronics, ISNE 2016
Date Issued
2016
Author(s)
Abstract
We report on the structural and electronic properties of a series of GaAs 1-x N x with wide x range. The alloys were grown on (001) GaAs substrate using plasma-assisted molecular beam epitaxy. Transmission electron microscopy and selective area electron diffraction (SAD) were used to probe the crystalline of GaAs 0.496 N 0.504 sample. The results indicate that the alloy is polycrystalline and amorphous. In the polycrystalline observed zinc-blende (ZB) and hexagonal structure. In this result, we suggest generation of miscibility and phase separation from two kind of structure. Calculation the vertical and horizontal lattice constant with x in the range from 0.106-0.848. Observed the az is dramatic drop with increase N content and a xy slow decrease, we suggest this result relation of nitrogen cluster alone [001] and residual horizontal substrate strain. Photo-modulated reflectance spectroscopy was used to determine the energy gap of the GaAs 1-x N x alloys, which ranges from 0.7-2.0 eV, covering a large part of the solar spectrum. The energy gap is in agreement with BAC model.
SDGs
Type
conference paper