Preparation of Functionalized Semiconductor Thin Film by Laser-Induced Surface Reaction

采用脉冲束化学气相沉积方法，以四异丙醇钛和h2o气相沉积TiO_2薄膜。每一种反应物气体被引入一个室交替使用商用汽车电动燃料喷射器作为光束源。这些薄膜在不同的衬底温度下沉积，用光学吸收光谱、x射线衍射和x射线光电子能谱对其进行了表征。并与电子束蒸发法制备的TiO_2薄膜进行了性能比较。采用电子束蒸发法在ITO（铟锡氧化物）玻璃衬底上生长了掺杂Al和共掺杂Al- in的ZnS薄膜电极，并对其光电化学性能进行了研究。并用光学吸收、x射线衍射（XRD）和x射线光电子能谱（XPS）对薄膜进行了表征。仅用Al掺杂ZnS薄膜不能得到令人满意的n型半导体。而在ITO玻璃基板上沉积一层薄薄的In层进行热扩散制备的Al-In共掺杂ZnS薄膜，ITO与ZnS之间的阻挡电阻降低，并观察到明显的n型半导体特性。随着铝浓度的增加，ZnS在水溶液中的光电流效率和光腐蚀效率均有所提高。

TiO_2 thin films were deposited by pulsed beam chemical vapor deposition from titanium tetraisopropoxide and H_2O vapors. Each reactant gas was introduced to a chamber alternately using commercial automobile electric fuel injectors as a beam souece. These thin films, deposited at various substrate temperatures, were characterized by optical absorption spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy. Their properties were compared with those of TiO_2 films deposited by electron beam evaporation.Al doped and Al-In co-doped ZnS thin film electrodes were grown by electron-beam evaporation on ITO (indium-tin oxide) glass substrate, and their photoelectrochemical properties were investigated. These thin films were also characterized by optical absorption, X-ray diffraction (XRD) and X-ray photoelectron spectrum (XPS) measurements. The doping of the ZnS film with Al alone did not result in a satisfactory n-type semiconductor. For Al-In co-doped ZnS thin films prepared by the thermal diffusion of a thin In layr which was deposited previously on the ITO-glass substrate, however, the barrier resistance between ITO and ZnS was lowered, and a clear n-type semiconductor characteristic was observed. The efficiencies of both the photocurrent and photocorrosion of ZnS in an aqueous electrolyte were increased with higher Al concentration.