Abstract
Cathodoluminescence (CL) of rare earth (RE) ions implanted AlN/GaN superlattice (SL) structures grown by chemical vapor deposition (CVD) technique on GaN/(0001) sapphire substrate was measured at 10 K and 300 K. Implantation of terbium and thulium in SLs was done at 150 keV with a dose of up to 1x10 super(15) cm super(-2) at 300 K. Samples were given post implantation isochronal thermal treatment at 900 C in nitrogen ambient. The interface quality between the SL layers before and after implantation as well as after thermal annealing treatment has been investigated by X-ray diffraction (XRD). The characteristic satellite peaks of the SLs were measured for the (0002) reflection in the symmetric Bragg geometry for the reference, RE-implanted, and annealed SLs. Furthermore, the luminescence intensity of a RE super(3+) ion doped AlN/GaN SL was compared with the one from RE-implanted GaN epilayers. Despite the structural damage of the AlN/GaN structures, an enhancement of the characteristic emission intensities from RE super(3+) ions in the SLs was observed compared to emission from RE ions in epilayers.