STRUCTURE EFFECTS ON THE OPTICAL PROPERTIES OF THIN (PbLa)TiO_3 FILMS

摘要

Amorphous thin films of Pb_(1-x)La_xTiO_3 (with x=0, 13 and 27 mol %) were prepared by the polymeric precursor method and deposited by spin coating on glass substrates. The films were characterized by X-ray diffraction (XDR) and scanning electron microscopy (SEM) and the band gap energy of the amorphous PLT films was calculated from the UV-VIS spectra. The obtained values were compared to that theoretically calculated. The observed decrease of the band gap was attributed to increased density of defects in the amorphous structure. Fu-thermore photoluminescence (PL) at room temperature was observed for thin (PbLa)TiO_3 films