Optical excitation of Er3+ ions in a-SiN alloys

Photoluminescence excitation spectroscopy was carried out on the I-4(13/2)- ->I-4(15/2) transition from Er-doped amorphous silicon-nitrogen thin film a lloys (a-SiN). The sample was prepared by cosputtering of a Si target parti ally covered with Er pellets. It is demonstrated that Er3+ ions may be exci ted by direct sharp-line intra-4f-shell absorption as well as by energy tra nsfer from the a-SiN matrix. The effects of temperature and possible energy transfer mechanisms to Er ions are presented and discussed. (C) 1999 Ameri can Institute of Physics. [S0021-8979(99)01713-2].