Characteristics of thulium doped gallium oxide films grown by pulsed laser deposition

Thulium (Tm) doped Ga2O3 films were deposited on sapphire substrates by pulsed laser deposition (PLD) with changing Tm compositions in the targets. Energy dispersive spectroscopy results reveal that films with different Tm compositions can be tailored by changing the Tm composition in the targets. X-ray diffraction and Raman spectra analysis indicate that all films have the monoclinic structure. Photoluminescence measurements demonstrate that the emission peaks at 460, 650 and 800 nm are observed from the Tm3 + 4f intrashell transitions from 1G4 excited states to the 3H6, 3F4, and 3H5 states, respectively. The results suggest that PLD is a promising method for obtaining high quality Tm doped Ga2O3 films, which paves the way for the fabrication of optoelectronic devices based on Ga2O3 films.