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ZnO thin film has been fabricated on sapphire substrate (0001) using RF magnetron sputtering at room temperature. The influence of sputtering power ranging from 10 W to 70 W on the microstructural and optical properties of ZnO films is investigated by atomic force microscopy (AFM), X-ray diffraction (XRD), ultraviolet-visible spectrophotometer. The AFM results show that with the increase of sputtering power, the size of ZnO crystalline increases first, then decrease and the maximum grain size occurs at 50 W. The XRD measurements indicate that the ZnO films with wurtzite structure are highly c-axis orientation and the film fabricated at 50 W has the best crystalline quality. Optical transmission spectra of the ZnO samples demonstrate that the ZnO film obtained at 50 W has the higher average transmission (above 90%) in the visible-light region and its optical band gap is 3.26 eV.

We have investigated systematically the oxygen pressure dependences of the crystalline phases and the crystallographic orientations of BaTiO3 thin films by means of asymmetric rocking curves. Epitaxial BaTiO3 thin films were grown on SrTiO3 (001) substrates by pulsed laser deposition (PLD) under different oxygen pressures. The X-ray diffraction theta/2 theta scans showed no diffraction peaks from impurity phases or randomly oriented grains, indicating that the thin films were single phase BaTiO3. The XRD omega rocking curves indicated that the BaTiO3 thin films had a very high degree of crystallinity. The XRD phi scans showed that no in-plane misorientation existed in the BaTiO3 thin films. The results of asymmetric rocking curves showed that the BaTiO3 thin films grown under higher oxygen pressures(> 12 Pa) were tetragonal with a-axis orientation, those grown under lower oxygen pressures (

Epitaxial BiFe 0.95 Mn 0.05 O 3 (BFMO) film was deposited on (001)-oriented SrRuO 3 (SRO) coated SrTiO 3 (STO) substrate by radio-frequency (rf) magnetron sputtering. Indium tin oxide (ITO) was grown on BFMO/STO heterojunction to fabricate ITO/BFMO/SRO capacitor for investigating the ferroelectric and photovoltaic properties. The ITO/BFMO/SRO capacitor exhibits large remanent polarizations of 92.2 μC/cm2, 101 μC/cm2 and 109 μC/cm2 measured at 20 V, 25 V and 30 V, respectively. An observed abnormal capacitance–voltage (C–V) curve can be explained based on the ITO/BFMO interface. The calculated capacitance and junction width of ITO/BFMO interface are 105 pF and 32 nm, respectively. Additionally, it is found that photovoltaic effect of the ITO/BFMO/SRO capacitor is mainly attributed to ferroelectric polarization and internal electric field induced by defects. The photocurrent densities coming from ferroelectric polarization and internal field are 36 μA/cm2 and 23 μA/cm2, respectively. The photovoltaic output from the ferroelectric polarization is obviously larger than that from the internal electric field.

Ta (3.3 nm)/ Ni – Al (3.3 nm) integrated films deposited on Si substrates by magnetron sputtering, annealed at various temperatures in a ultra-high vacuum, have been studied as diffusion barrier layers between Cu and Si for application in Cu interconnection. The images of transmission electron microscopy (TEM) prove that the cross-sectional interfaces of Cu / Ta / Ni – Al / Si sample annealed at 600°C are clear and sharp. No Cu –silicide peaks can be found from the X-ray diffraction (XRD) patterns of the 850°C annealed sample, but the sheet resistance of the sample increases abruptly. Moreover, large grooves are found from the image of atomic force microscopy (AFM) for the 850°C annealed sample, implying the failure of the diffusion barrier. The integrated Ta / Ni – Al barrier layer retains thermally stable nature up to at least 800°C, indicating that the Ta / Ni – Al integrated film is an excellent diffusion barrier between Cu and Si .