Thermal doping of rare-earth ions in gallium nitride

Abstract

Doping of rare-earth ions in epitaxial gallium nitride material has been performed through a thermal diffusion process. The technique involves a brief photolytic etching of the surface followed by heating with a melt of rare-earth salt under reducing conditions. Europium-doped GaN pumped with above gap UV radiation showed strong red emission which was insensitive to a moderately strong magnetic field. The temperature dependence of the intensity of this red emission is also described. Neodymium caused surface pitting, through an unknown chemical mechanism, and consequent enhancement of defect-generated yellow luminescence.