Nature of the 2.8-eV photoluminescence band in Si-doped GaN

Article

关键词: YELLOW LUMINESCENCE;    EPITAXIAL-FILMS;    DEFECTS;    VACANCIES;    ORIGIN;    OXYGEN;   

DOI  :  10.1103/PhysRevB.62.12593

来源: SCIE

【 摘 要 】

Investigation on the defect-related luminescence centered around 2.8 eV in Si-doped GaN epifilms is pre sented. It is found that: the mechanism of this blue emission (BL) is quite different from that of the yellow luminescence (YL). By comparing the photoluminescence (PL) spectra obtained from either front-side or backside excitation and combining with the results of the BL and YL-related PL excitation and the secondary-ion-mass spectroscopy measurements, we propose that the 2.8-eV emission is the transition from the substitutional oxygen donor(O-N) level at 0.25 eV above the conduction band to the V-Ga-O-N complex acceptor. The energy level of the VGa-ON complex is found to be at 0.8 eV above the valence-band edge which is consistent with the theoretical calculation. In addition, we show that the V-Ga defect plays a key role in the link between the time evolution of the YL and BL spectra in GaN samples.

【 授权许可】

Free