Optical properties of magnetron sputtered Tb3+ ions containing thin dielectric films for thin film solar cells applications

Abstract

Results are presented on the deposition and characterization of thin SiO2 and Al2O3 films containing Tb3+ ions developed for application as spectral converters. The films are prepared by RF magnetron co-sputtering. The photoluminescence (PL) is measured at room temperature using the 488 nm line of an Ar laser. The dependence is studied of the PL intensity on the Tb concentration in the film. It is found that the intensity exhibits a maximum at about 1 at.%. Annealing studies are performed on SiO2:Tb using two different methods to improve the PL intensity. In both regimes of annealing, the best results are obtained at 650 − 700°C. After treatment at this temperature the Tb PL increases 2.5 − 3 times.