Temperature-dependent photoluminescence properties of amorphous and crystalline V₂O₅ films

Abstract

In order to investigate the photoluminescence (PL) properties of V 2 O 5 films, amorphous and crystalline films were prepared by using RF sputtering system, and the PL spectra of the films were measured at the temperatures ranging from 300 K to 10 K. In the amorphous V 2 O 5 film grown at room temperature, a PL peak centered at ~505 nm was only observed, and in the crystalline V 2 O 5 film, two peaks centered at ~505 nm and ~695 nm, which is known to correspond to oxygen defects, were revealed. The position of PL peak centered at 505 nm for both the amorphous and crystalline V 2 O 5 films showed a strong dependence on temperature, and the positions were 2.45 eV at 300 K and 2.35 eV at 10 K, respectively. The PL at 505 nm was due to the band energy transition in V 2 O 5, and also, the reduction of the peak position energy with decreasing temperature was caused by a decrement of the lattice dilatation effect with reducing electron-phonon interaction.