Deep levels introduced in n-GaN grown by the ELOG technique by high-energy electron irradiation

Abstract

We have used deep level transient spectroscopy (DLTS) to investigate the electron trap defects introduced in n-GaN grown, using the epitaxial lateral overgrowth technique during high-energy electron irradiation from a 90Sr radionuclide source. The results indicate that, apart from the major defect with an energy level at 0.20 eV below the conduction band (supposed to be related to the V N), at least four other defects with energy levels centered about 0.90±0.15 eV, are introduced. From modeling, ignoring temperature dependent capture cross-section effects we have determined their activation energies, and temperature independent capture cross sections, commonly known as the DLTS signature.