Raman Measurements and Stress Analysis in Gallium Ion Implanted Gallium Nitride Epitaxial Layers on Sapphire

TL;DR

This study uses Raman spectroscopy to measure hydrostatic stress and analyze phonon interactions in gallium nitride layers implanted with gallium ions, revealing stress effects, deformation potentials, and phonon-plasmon coupling.

Contribution

It provides new insights into stress estimation, deformation potential constants, and phonon-plasmon interactions in gallium nitride epitaxial layers post-implantation.

Findings

Hydrostatic stress quantified via Raman measurements.

Deformation potential constants calculated for E2(high) mode.

Evidence of polar phonon-plasmon coupling in the system.

Abstract

In this article, we estimate hydrostatic stress developed in gallium ion implanted gallium nitride epitaxial layers using Raman measurements. We have calculated deformation potential constants for $E_2$(high) mode in these epi-layers. The presence of a polar phonon-plasmon coupling in these systems has also been demonstrated. In as-implanted samples, with an increase in implantation fluence, we have observed disorder-activated Raman scattering.