ION-BEAM EXCITED LUMINESCENCE OF SAPPHIRE

Ion implantation of sapphire produces not only the F and F+ colour centres but also more complex defect structures. Luminescence recorded during implantation is capable of detecting the transient concentrations of these defects. Measurements of the luminescence signals produced by H+, H2+, He+ O+ and Ar+ ion beams show evidence for the familiar F and F+ defects. An additional weak signal is attributed to an F2-type defect. However, the signal intensities are not a direct measure of the defect concentrations as the recorded light intensities are a function of the ion species, ion dose, implant temperature, crystal cut and the polarisation of the emitted light. It is suggested that stress generated by the implant reduces the luminescence efficiency, this being most noticeable for the F emission. © 1990.