Incorporation and optical activation of Er in group III-N materials grown by metalorganic molecular beam epitaxy

Metalorganic molecular beam epitaxy has been utilized to incorporate Er into AlGaN materials during growth utilizing elemental and metalorganic sources. Room temperature 1.54 mu m photoluminescence was observed from AlN:Er and GaN:Er. Photoluminescence from AlN:Er doped during growth using the elemental source was several times more intense than that observed from implanted material. For the first time, strong room temperature 1.54 mu m PL was observed in GaN:Er grown on Si. Temperature-dependent photoluminescence experiments indicated the 1.54 mu m intensities were reduced to 60% and 40% for AlN:Er and GaN:Er, respectively, between 15 K and 300 K. The low volatility of Er(III) tris (2,2,6,6-tetramethyl heptanedionate) and temperature limitations imposed by transport considerations limited maximum doping levels to similar to 10(17) cm(-3) indicating that this precursor is unsuitable for UHV.