Optical characterization of GaN by N+ implantation into GaAs at elevated temperature

TL;DR

This study demonstrates the synthesis and characterization of GaN phases in GaAs through N+ implantation at elevated temperatures, revealing phase formation, structural properties, and optical behavior.

Contribution

It introduces a method for creating mixed-phase GaN in GaAs using high-energy N+ implantation and detailed characterization of the resulting phases.

Findings

GaN phases formed at fluence > 2x10^17 cm^-2

Sharp photoluminescence peak at ~3.32 eV at low temperatures

Presence of mixed hexagonal and cubic GaN phases

Abstract

Both hexagonal wurtzite and cubic zinc blend GaN phases were synthesized in GaAs by 50 keV N+ implantation at 400 deg C and subsequent annealing at 900 deg C for 15 min in N2 ambient. Crystallographic structural and Raman scattering studies revealed that GaN phases were grown for fluence above 2x1017 cm-2. Temperature-dependent photoluminescence study showed sharp direct band-to-band transition peak ~3.32 eV at temperature <= 200K. The intermediate bandgap value, with respect to ~3.4 eV for hexagonal and ~3.27 eV for cubic phases of GaN is an indicative for the formation of mixed hexagonal and cubic phases.