The intensity of the photoluminescence of erbium in silicon is analyzed by
a model which takes into account the formation of free excitons, the bindin
g of excitons to erbium ions, the excitation of inner-shell 4f electrons of
erbium ions and their subsequent decay by light emission. Predictions of t
his model for the dependence of luminescence intensity on laser excitation
power are compared with experimental observations. The results for float-zo
ne and Czochralski-grown silicon, in which erbium is introduced by implanta
tion with or without oxygen co-implantation, are remarkably similar. To obt
ain agreement between model analysis and experimental data it is necessary
to include in the model terms describing energy dissipation by an Auger pro
cess of both the erbium-bound excitons and the erbium ions in excited state
with free electrons in the conduction band. A good quantitative agreement
is achieved. (C) 1999 American Institute of Physics. [S1063-7826(99)00306-3
].