Characterization and annealing of Eu-doped GaN

Red emission at 621 nm from the D-5(0) --> F-7(2) transition of Eu+3 has been obtained from GaN:Eu grown by gas-source molecular beam epitaxy. The luminescence has been found to be more intense than the red emission from metalorganic chemical vapor deposition (MOCVD) derived AlGaAs. Upon annealing in both N-2 and N-2/H-2 mixtures up to 800 degreesC, the integrated photoluminescence (PL) intensity was found to remain within a factor of 2 of the as grown sample. The surface morphology also remained unchanged. Thermal quenching measurements of the as-grown sample saw a reduction in the 621 nm emission of 82% as the measurement temperature was increased from 20 to 300 K. The quenching was reduced to 66% after annealing at 800 degreesC. (C) 2001 Elsevier Science B.V. All rights reserved.