Photoluminescence characterization of Er-implanted Al2O3 films

Al2O3 films on oxidized Si substrates were implanted with 800 keV Er ions to peak concentrations ranging from 0.01 to 1 at. %. The samples show relatively broad photoluminescence spectra centered at λ=1.533 μm, corresponding to intra‐4f transitions in Er3+. At an Er peak concentration of 0.23 at. %, post‐implantation thermal annealing up to 950 °C increases the photoluminescence intensity by a factor 40. This is a result of defect annealing, which increases the luminescence lifetime from 1 to 7 ms, as well as an increase in the Er3+ active fraction. High Er concentrations are achieved with only moderate concentration quenching effects.