Erbium-doped GaN epilayers synthesized by metal-organic chemical vapor deposition

The authors report on the synthesis of Er-doped GaN epilayers by in situ doping by metal-organic chemical vapor deposition (MOCVD). The optical and electrical properties of the Er-doped GaN epilayers were studied by photoluminescence (PL) spectroscopy and van der Pauw-Hall method. Both above and below band gap excitation results in a sharp PL emission peak at 1.54 μm. In contrary to other growth methods, MOCVD grown Er-doped GaN epilayers exhibit virtually no visible emission lines. A small thermal quenching effect, with only a 20% decrease in the integrated intensity of the 1.54 μm PL emission, occurred between 10 and 300 K. It was found that Er incorporation has very little effect on the electrical conductivity of the GaN epilayers and Er-doped layers retain similar electrical properties as those of undoped GaN.