Capacitance-voltage profiles, admittance spectra, deep-level spectra, current-voltage characteristics, and microcathodoluminescence (MCL) spectra were measured before and after electron irradiation of n-GaNInGaN multi-quantum-well (MQW) structures typical of the active region of GaNInGaN blue light emitting diodes. Electron irradiation produces strong compensation of the conductivity in the MQW and introduces interface traps with ionization energies of 100 and 190 meV, in addition to a broad band of interface traps closer to the middle of the bandgap, acceptor traps near Ec -1.1 eV and hole traps near Ev +0.9 eV in the GaN barriers and at the GaNInGaN interfaces in the QWs. The dose of electrons at which measurable changes occur in the MCL spectra is 1015 cm-2, while measurable changes in the electrical properties are observed after doses exceeding 1016 cm-2 electrons.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films
- Materials Chemistry