PHOTOLUMINESCENCE OF ERBIUM-IMPLANTED GAN AND IN SITU-DOPED GAN-ER

The photoluminescence of in situ-doped GaN:Er during hydride vapor pha se epitaxy was compared to an Er-implanted GaN sample. At 11 K, the ma in emission wavelength of the in situ-doped sample is shifted to short er wavelengths by 2.5 nm and the lifetime is 2.1+/-0.1 ms as compared to 2.9+/-0.1 ms obtained for the implanted sample. The 295 K band edge luminescence of the in situ-doped sample was free of the broad band l uminescence centered at 500 nm which dominated the spectrum of the imp lanted sample. Reversible changes in the emission intensity of the in situ-doped sample upon annealing in a N-2 versus a NH3/H-2, ambient in dicate the probable role of hydrogen in determining the luminescence e fficiency of these samples. (C) 1998 American Institute of Physics. [S 0003-6951(98)02010-5].