Effect of Tb-doping on the nano-structural and optical features of nano-crystalline Si thin films

The nano-structural and optical features of Tb-doped Si (Tb:Si) thin films, which were prepared by RF magnetron sputter techniques, were investigated as a function of Tb-contents and post-deposition heat-treatment conditions. The structural and chemical features are related with the photoluminescence (PL) phenomena of the films. The PL intensity increased with the amount of Tb3+ as well as Si nano-crystallites in the films. A strong PL peak was observed at about 545 nm owing to the electronic structure of Tb3+. Post-deposition heat-treatment increased the fraction of nano-crystallites of less than 10 nm in size; this resulted in enhancing the PL generated by the intra-4f Tb3+ transition.