Effect of the Er-Si interatomic distance on the Er 3+ luminescence in silicon-rich silicon oxide thin films

The photoluminescencePL intensity of Er-doped silicon monoxide thin films obtained by
coevaporation of silicon monoxide and Er is studied for different deposition and annealing
atmosphere compositions. All samples exhibit a luminescence peak at 1.54 m assigned to the
radiative deexcitation of Er 3+ . PL intensity is highest when nitrogen atoms are incorporated in the
layer during deposition. Extended x-ray absorption fine structure spectroscopy evidences that the
local order around the erbium ion is modified in the presence of nitrogen. In particular, the shorter
the Er-Si interatomic distance is, the higher the Er
3+PL intensity is.