Anisotropic charge transport in non-polar GaN QW: polarization induced charge and interface roughness scattering

TL;DR

This paper investigates anisotropic charge transport in non-polar GaN quantum wells, highlighting how surface roughness and polarization effects cause directional differences in carrier mobility, which diminish at higher temperatures due to phonon scattering.

Contribution

It introduces a theoretical model for anisotropic line charge scattering caused by surface morphology and polarization in non-polar GaN QWs, revealing temperature-dependent transport anisotropy.

Findings

Anisotropic transport is significant at low temperatures.

Surface roughness and polarization induce anisotropic scattering.

High temperatures reduce anisotropic effects due to phonon scattering.

Abstract

Charge transport in GaN quantum well (QW) devices grown in non-polar direction has been theoretically investigated . Emergence of anisotropic line charge scattering mechanism originating as a result of anisotropic rough surface morphology in conjunction with in-plane built-in polarization has been proposed. It has shown that in-plane growth anisotropy leads to large anisotropic carrier transport at low temperatures. At high temperatures, this anisotropy in charge transport is partially washed out by strong isotropic optical phonon scattering in GaN QW.