Changes in G-line (0.9695eV) and C-line (0.7894eV) photoluminescence intensities were studied as a function of the fluence, energy and mass of the ions (He, Ne, Ar, Kr). The intensities of the luminescent lines which were induced by 1keV Ne bombardment were found to decrease with increasing dose after reaching a maximum at about 1012/cm2. Appreciable reductions in the intensities of the G- and C-lines were also recorded during bombardment using heavier noble gas ions, and this was attributed to the higher rates of nuclear energy deposition with increasing ion mass. The incident ion energy at which the photoluminescence intensities of the spectral lines reached their maximum values depended upon the ion mass and fluence. The decreases in the photoluminescence intensities of the G-line and C-line were explained in terms of the introduction of increased amounts of non-radiative recombination centers with increasing incident ion dose and mass. The integral sum of defects which were induced during bombardment, as a function of projected ion range and excitation depth of the Ar-ion laser, was used to describe qualitatively the decrease in the intensities of the two lines.

P.N.K.Deenapanray, N.E.Perret, D.J.Brink, F.D.Auret, J.B.Malherbe: Journal of Applied Physics, 1998, 83[8], 4075-80