Influence of thermal annealing on the intensity of the 1.54-μm photoluminescence band in erbium-doped amorphous hydrogenated silicon

Erbium-doped a-Si:H films are prepared by magnetron sputtering of a Si-Er target at a deposition temperature of 200 degrees C. The films are then subjected to cumulative thermal annealing. A sharp increase (similar to 50-fold) in the photoluminescence intensity at a wavelength of 1.54 mu m is observed after a 15-min anneal at 300 degrees C in a nitrogen atmosphere. At an anneal temperature greater than or equal to 500 degrees C the photoluminescence signal decreases essentially to zero. The influence of thermal annealing processes is discussed in the context of the model of partial transformation of the structural network of amorphous a-Si(Er):H films. (C) 1999 American Institute of Physics. [S1063-7826(99)02201-2].