InN/GaN valence band offset: High-resolution x-ray photoemission spectroscopy measurements

Abstract

High-resolution x-ray photoemission spectroscopy measurements are used to determine the valence band offset of wurtzite-InN/GaN(0001) heterojunctions to be $0.58\ifmmode\pm\else\textpm\fi{}0.08\text{ }\text{eV}$. This is discussed within the context of previous measurements and calculations and is in agreement with the value of $0.52\ifmmode\pm\else\textpm\fi{}0.14\text{ }\text{eV}$ determined from the alignment of the experimentally determined charge neutrality levels in InN and GaN. The heterojunction forms in the type-I straddling configuration with a conduction band offset of $2.22\ifmmode\pm\else\textpm\fi{}0.10\text{ }\text{eV}$.