Effects of dopant concentration on structural and near-infrared luminescence of Nd~(3+)-doped beta-Ga_2O_3 thin films

摘要

We have investigated structural and near-infrared (MR) luminescence of Nd~(3+)-doped β-Ga_2O_3 thin films (Nd:Ga_2O_3) with different Nd~(3+) doping concentrations. With an increase of Nd~(3+) content, the crystal lattice of the films expands, while the energy band gap shrinks. Moreover, NIR luminescence is investigated as a function of Nd~(3+) doping concentration. The measured results are related to the structural change and energy transfer of cross relaxation process ascribed to ~4F_(3/2)-~4I_(9/2), ~4F_(3/2)-~4I_(11/2). and ~4F_(3/2)-~4I_(13/2) of the phosphor films. This work implies that the enhanced NIR luminescence and blue-shift observation are associated with the lattice distortion and the variation in the crystal field of Nd: Ga_2O_3.