Native defects in InxGa1-xN alloys

To elucidate the role of native defects in determining the electronic and optical properties of In1-xGaxN, energetic particle irradiation (electrons, protons, and He-4(+)) has been used to intentionally introduce point defects into InxGa1-xN alloys. Optical absorption, Hall effect, and capacitance-voltage (CV) measurements are used to evaluate properties of these materials. Irradiation produces donor-like defects in InxGa1-xN with x > 0.34, while acceptor-like defects form in Ga-rich InxGa1-xN (x < 0.34). A sufficiently high irradiation dose pins the Fermi level at the Fermi level stabilization energy (E-FS), as predicted by the amphoteric defect model. Pinning of the Fermi level at this energy is also responsible for the surface electron accumulation effect in unirradiated In-rich In1-xGaxN. (c) 2005 Published by Elsevier B.V.