| ZnO, SnO2 and TiO2, are typical novel oxide semiconductors with band gaps of 3eV above at room temperature and large exciton binding energies. They have excellent photonelectronic properties; have many protencial applications in transparent conducting films, for instance, photocatalysis, surface acoustic wave devices, liquid crystal display, gas sensors and photoelectronic devices. The reports of ultraviolet laser emission of high quality SnO2, TiO2, ZnO thin films at room temperature promoted people's interesting in oxide semiconductors researching.In the thesis, we report that SnO2, TiO2, ZnO thin films prepared by pulsed laser deposition (PLD) and the growth conditions are optimized. Furthermore, we employ X-ray diffraction, Raman spectroscopy, Photoluminescence Spectroscopy, SEM, laser induced voltage (LIV) and resistance & temperature (R-T) behaviors to investigate the influence of different growth conditions on structures, electric properties of these thin films. The major results are listed as the following:1. Structures of SnO2 thin films and investigation of their structures and transport propertiesWe have prepared highly a-axis oriented SnO2 and Fe doped SnO2 thin films on sapphire substrates, and investigated the crystallinities of SnO2 and Fe doped SnO2 thin films. The X-ray rocking curves results indicate that the prepared SnO2 thin film are with good crystallinity at the optimized growth conditions. For the first time, the transverse laser induced voltages are detected in the tilted SnO2 thin films and a signal of 4V was observed on tilted substrates at 100mJ/cm2, with the rising time about 28ns and responding time around 98ns. The structures of SnO2 thin films remained stability after operated with the high energy UV laser, and the resistance & temperature behaviors curves indicate that the SnO2 thin films with low TCR, and nice heat stabilization.2. Growth of ZnO thin films on Si substrates and investigation of their structures and transport propertiesWe have prepared highly c-axis oriented ZnO on Si substrate at different growth conditions, such as substrate temperature, oxygen partial pressure, laser energy and deposited time, and investigated the effects of the growth condition on the crystallinity of ZnO thin films, and analyzed the reason of the influence. Then we prepared ZnO thin film with good crystallinity at the optimized growth condition. X-ray rocking curve result indicates that the FWHM of its (002) peak is 0.2°. Moreover we used Raman and PL spectrum to study the structures and optical properties, Raman spectrum recorded 6 overtones of LO mode, the results suggest that ZnO thin films with good quality at high substrate temperature. Furthermore, PL spectra results suggest that the emission of ZnO is relative to its crystallinity. The transverse laser induced voltages are detected in the ZnO thin films grown on the tilted substrates, and the signal of 0.18V at 100mJ/cm2 with the rising time about Ins and responding time about 58ns, and its structure not deteriorated after the laser operated with high energy. The maximal TCR reached -13% K-1, which indicated that ZnO thin films have great potential application in Bolometer.3. Preparing ZnO thin films on Al2O3 and studying their transport propertiesWe have grown highly c-axis ZnO thin films on Al2O3 at different substrate temperatures and oxygen pressures by PLD. XRD and rocking curve have been employed to investigate the influence of substrate temperature and oxygen pressure on the crystallinity and growth mode of ZnO thin films. X-ray rocking curve results exhibit that the FWHM of (002) peak of ZnO thin films only 0.2°, indicating that the ZnO thin film is single crystal.The transverse laser induced voltages are detected in the tilted ZnO thin films and the signal of 0.3V at 100mJ/cm2 with the rising time about 33ns and responding time about 167ns, and its structure not deteriorated after the laser operated with high energy.4. Influence of Co-doped on the structures and transport properties of ZnO thin filmsHighly c-axis oriented Zn1-xCoxO(x=0.005,0.05,0.10,0.15,0.33) thin films have been fabricated on Si and Al2O3 substrates by pulsed laser deposition. X-ray diffraction has been employed to characterize the influence of Co-doping on structure properties of ZnO thin films. The results indicate that Zn1-xCoxO, alloy formed after Co doped in ZnO. Co atoms have entered into the ZnO crystal lattice and substituted Zn atoms with Co2+ or Co3+ states. The transverse laser induced voltages are detected in the tilted Zn1-xCoxO thin films and the signal of 0.5V at 100mJ/cm2 with the responding time about 177ns, and its structure not deteriorated after the laser operated with high energy. The maximal TCR reached -20% K-1, which made it have great potential application in Bolometer. No report has been found as we known.5. Influence of Ag-doped on the structure and transport properties of ZnO thin filmsHighly c-ax is oriented Zn1-xAgxO(x=0.005,0.01,0.03,0.05,0.10) thin films have been fabricated on Si and Al2O3 substrates by pulsed laser deposition. X-ray diffraction has been employed to characterize the influence of Ag-doping on structure properties of ZnO thin films. The results indicate that Zn1-x AgxO, alloy formed after Ag doped in ZnO. Ag atoms have entered into the ZnO crystal lattice. The transverse laser induced voltages are detected in the tilted Zn1-x AgxO thin films and the signal of nearly 2V at 100mJ/cm2 with the responding time reducing with the increasing of Ag contents, and its structure not deteriorated after the laser operated with high energy. The maximal TCR reached -17.5% K-1, which made it have great potential apply in Bolometer. 6. Structures of TiO2 thin films and investigation of their structure and transport propertiesHighly c-axis oriented TiO2 thin films of anatase structures have been fabricated on LaA103 substrates and highly a-axis oriented TiO2 thin films of rutile structures have been fabricated on Al2O3 substrates by pulsed laser deposition. For the rutile TiO2 thin films,θof its (200) peak is 19.71°, and FWHM of its (200) peak is 0.19°, and it is indicate that the TiO2 thin films with high crystallinity, and close to single crystal. The maximal TCR reached -6.3% K-1. For the first time, the transverse laser induced voltages are detected in the tilted TiO2 thin films and the signal of 1.58V at 100mJ/cm2 with the responding time about 395ns, and its structure stabilization remained after the laser operated with high energy.And for the anatase TiO2 thin films,θof its (200) peak is 18.84°, and FWHM of its (200) peak is 0.27°, and the resistance & temperature behaviors curves indicate that the anatase TiO2 thin films have low TCR, and nice heat stabilization.
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