Weak localization in indium nitride films

Abstract

ABSTRACT We have studied the weak localization (WL) effects in the electron accumulation layer on InN surface. Both the spin-orbit relaxation time 2 so and the electron-phonon scattering time 2 e-ph have been extracted from the WL analysis. We have observed that 1/2 so increase with disorder and 2 e-ph exhibits a tendency to change gradually from the characteristic dependence 1/ 2 e-ph 3v 2T in the pure case to the form of T l -1 with increasing disorder. Keywords: indium nitride, electron accumulation layer, weak localization, electron-phonon scattering time 1. INTRODUCTION As an important group-III nitride semiconductor, indium nitride (InN) has attracted much attention over the last few years due to its very prospective properties. One of its unique characteristics is the existence of surface electron accumulation [1], which would qualitatively change the behavior of optical and electrical properties in InN films. The high electron concentration and poor lattice quality make this ex tra layer an ideal disorder system for investigating weak localization (WL) effects. WL has attract ed great attention since it was first theoretically predicted and experimentally demonstrated [2], because it provides th e information of the various phase-rela xation mechanisms of the electron wave functions, especially the electron-phonon (e-ph) relaxation time. However, present studies about the e-ph interactions mostly focus on the limiting cases (dirty limit q