Effects of oxygen pressure on La3Ga5SiO14 thin films grown by pulsed laser deposition

Abstract La 3 Ga 5 SiO 14 thin films were grown on Si (100) substrates by pulsed laser deposition at several oxygen pressures (5, 10, and 20 Pa). The effects of oxygen pressure on the structural and morphological characteristics of the films were investigated using X-ray diffraction, atomic force microscopy, and scanning electron microscopy. X-ray diffraction results showed the intensity of lines from crystallites oriented along the (300) and (220) planes increased as the oxygen pressure was increased to 20 Pa. The deposited films exhibited smooth surface as observed by atomic force microscopy and scanning electron microscopy. Photoluminescence measurements with 260 nm excitation showed that the films had emission in the ultraviolet and blue regions, and the luminescence intensity of the films increased with increasing oxygen pressured. We propose that these emissions originated from self-activated luminescence centers in the tetrahedral and octahedral Ga–O groups.