Defect related photoluminescence (PL) in unintentionally doped GaN layers grown by molecular beam epitaxy (MBE) was studied. Under certain growth conditions, we observed new defect-related bands: a red band with a maximum at about 1.88 eV and a green band with a maximum at about 2.37 eV. The quenching of these bands with increasing temperature took place with an activation energy of about 120-140 meV at temperatures above 100 K. Moreover, the red band exhibited an increase of PL intensity with an activation energy of 1.2 meV in the range of 10-60 K. The observed behavior is explained by invoking a configuration coordinate model and that we speculate the defects to be partially nonradiative and related to Ga atoms.
Photoluminescence Study of Defects in GaN grown by Molecular Beam Epitaxy
VISCONTI, Paolo;
2001-01-01
Abstract
Defect related photoluminescence (PL) in unintentionally doped GaN layers grown by molecular beam epitaxy (MBE) was studied. Under certain growth conditions, we observed new defect-related bands: a red band with a maximum at about 1.88 eV and a green band with a maximum at about 2.37 eV. The quenching of these bands with increasing temperature took place with an activation energy of about 120-140 meV at temperatures above 100 K. Moreover, the red band exhibited an increase of PL intensity with an activation energy of 1.2 meV in the range of 10-60 K. The observed behavior is explained by invoking a configuration coordinate model and that we speculate the defects to be partially nonradiative and related to Ga atoms.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
