Carrier Removal Rates and Deep Traps in Neutron Irradiated n-GaN Films

Carrier removal rates and deep trap spectra were measured in neutron irradiated n-GaN samples grown by metalorganic chemical vapor deposition (MOCVD), hydride vapor phase epitaxy (HVPE, and epitaxial lateral overgrowth (ELOG). The carrier removal rates were found to significantly increase with donor doping and to decrease in the sequence MOCVD/ ELOG/ HVPE. The most prominent traps created by irradiation were quasi-hole traps with energy 0.6–0.7 eV and electron traps with energy 0.45 eV. The former were associated with disordered regions in GaN and determine the carrier removal rate in undoped films. The latter were attributed to radiation defect complexes with shallow donors.