The Plt Thermoluminescence Study Of Thin Film Materials

Lead lanthanum titanate(PLT) ferroelectric thin film has superior pyroelectric, ferroelectric, piezoelectric and photoelectric characteristics, and it has been wildly used for various electromic equipments, such as pyroelectric IR detectors, dynamic random access memories(DRAMs) and electrooptic apparatus. In this work, the influences of fabrication process on microstructure, dielectric properties, ferroelectric properties and pyroelectric properties of PLT films have been studied.PLT films were prepared on the Pt(111)/Ti/SiO2/Si(100) substrates by radio frequency magnetron sputtering method and then annealed by rapid thermal annealing process(RTA) or conventional furnace annealing process(CFA).With the help of atom force microscopy (AFM), X-ray diffraction (XRD) and some other apparatus, it was found that: Lower substrate temperature (Ts) was helpful for PLT films to form better surface morphologies. With the increase of substrate temperature, the dielectric constant of PLT films increased. Compared with films annealed by CFA, films annealed by RTA showed a single perovskite phase and had better dielectric properties and ferroelectric properties. Even more, RTA shortened the heating time of PLT films. When the time of heat preservation prolonged, the intensity of most orientation of perovskite phase became stronger, and the full width at half maximum (FWHM) decreased. When the time of heat preservation was 80 seconds, the intensity of (100) and (110) orientation began to decrease. Generally speaking, the PLT films preserved for 60 seconds at 600℃was suitable, theirεr (dielectric constant), tanδ(loss tangent), Pmax (maximum polarization), Pr (remnant polarization), were 423, 2.1%, 27.5μC/cm2, 5.4μC/cm2 respectively.In this work, circle intermittent deposition was realized by periodical repetition of"deposition-nondeposition-annealing". Compared with the films deposited by continuous method, the surface of the films deposited by circle intermittent method was smoother and uniformer. And this method was effective to decrease the crystal temperature. It was found that the films deposited for 1 circle time after RTA at 600℃...