Development of Luminescent Nd-Doped LaNbO Compound Thin Film Growth by Magnetron Sputtering for the Improvement of Solar Cells

Abstract

Nd3+-doped LaNbO phosphor thin films were prepared by radio-frequency magnetron sputtering on Si substrates. The effects of a 1% Nd-doping concentration, after annealing at 1200 °C for 12 h, on the light-emitting properties of the sputtered thin films were characterized via several experimental techniques and deeply discussed. Photoluminescence characterization showed strong emission peaks typical of Nd3+ centers at 880 nm and 1060 nm when a 325 nm wavelength laser source was applied. Similar responses were detected in Nd3+-doped La3NbO7 powder samples fabricated by the solid-state reaction method. The coexistence of two phases (LaNbO4 and La3NbO7) in the thin films with higher nominal thickness was clearly identified based on different structural analyses. The promising results open the possibility for developing phosphor substrates as a preliminary step for the improvement of solar cells based on photon recycling mechanisms.