Boundary conditions for formation of Er-O optical centers in Er-and O-coimplanted Si

Photoluminescence (PL) of a variety of samples co-implanted with erbium and oxygen in FZ Si has been investigated to determine boundary conditions for the formation of Er-luminescent centers. Within a limited range of annealing temperatures, the formation of these centers can be controlled by the relative concentration of Er and O. As the annealing temperature increases from 600°C to 900°C for samples implanted with 1×10¹⁹ Er/cm³, the minimum concentration ratio of O/Er required for obtaining a PL intensity of the main line at 0.8068 eV from Er-centers increases from 0.1 at 700°C annealing to 10 at 900°C. We give evidence that oxygen migration is involved in enhancing the PL intensity of Er-optical centers. Preliminary Rutherford Backscattering spectroscopy and channeling (RBS/C) measurements give an experimental result on the lattice location of the Er³⁺ ions in samples dominated with cubic symmetry optical centers.