Er doping of GaN during growth by metalorganic molecular beam epitaxy

1.54 mu m photoluminescence has been observed from GaN doped with Er during growth by metalorganic molecular beam epitaxy, Strong Er3+-related photoluminescence (PL) was measured at room temperature for GaN:Er doped during growth on c-plane Al2O3 and Si. Experiments to evaluate the effects C and O on the optical activity of Er indicated that these impurities dramatically enhance Er PL in GaN. GaN films doped with Er to a concentration of 3x10(18) cm(-3) with [O] similar to 10(20) cm(-3) and [C] similar to 10(21) cm(-3) luminesce at 1.54 mu m with an intensity similar to 2 orders of magnitude greater than films with oxygen and carbon backgrounds of less than 10(19) cm(-3). The thermal PL quenching behavior was also markedly different for samples of varying O and C content. Er3+ luminescence from samples with high O and C concentrations quenched by only 10% between 15 and 300 K while the integrated PL signal from the samples with lower [O] and [C] quenched similar to 85% over the same temperature range. (C) 1998 American Institute of Physics.