| Zinc oxide(ZnO) is a new type of semiconductor material.Its gap width is about 3.37 eV at room temperature and its wavelength region which located near ultraviolet is transparent to visible light.The exciton binding energy of ZnO is 60 meV. ZnO can grow at relatively low temperatures, and the substrate used is varied.It can grow either in a single crystal substrate(such as sapphire, Si), can also be grown in the amorphous substrate(such as: glass, plastic).In addition to the single crystal and thin films, ZnO nanostructure is unusually rich,with a large specific surface area,and is ideal for sensors and detecting field. Moreover, ZnO has the advantages of simple etching process,high thermal stability, single crystal which is easy to get, so ZnO is a kind of green environmental protection material. Therefore, ZnO is considered to be a new generation of optoelectronic semiconductor material, and has become a new hotspot in the research on semiconductor materials and devices today.In this paper, we prepared ZnO nano arrays and films by the method of hydrothermal and chemical vapor deposition(CVD),and Al-doped ZnO, Ag/N dual-doping ZnO by coating method, and the preparation of heterogeneous p-n junction. Our research on the preparation of ZnO nano arrays and thin film,and its growth mechanism and related properties.The main research work and conclusions are as follows:1.ZnO seed layers are coated on a glass substrate using the dip-coating method, factors affecting the quality of the seed generated such as Zn2+concentration, solvent of Zn source,coating times, the annealing temperature are discussed in detailed research and analysis, and as a basis for optimizing the seed of the two-step preparation process. It was found that better quality ZnO seed layer can be obtained by the 0.01 M zinc acetate ethanol solution of 8-10 times, and annealed at 500 ℃.2. ZnO nanorods are prepared by hydrothermal in the different concentration solution and the CVD growth under different conditions with the seed layer as growth points, and SEM images of ZnO nano makes a preliminary discussion and analysis. Study found that with slide as substrate, hydrothermal growth method using a solution of 0.05 M constant temperature water bath at 95 ℃for 4 to 5h, can prepare ZnO nanorods and one-dimensional array which have good orientation, distribution of dense, and uniform diameter size. CVD method with0.005 M seed solution, three-zone tube furnace at a temperature of 800℃-450℃-450℃for 1h,O2 and Ar2 flow are 35 sccm and10sccm,can obtain a uniform particle size of ZnO thin film.3. ZnO nano film were prepared by coating method. Al-doped ZnO and(Ag, N) dual doping were prepared.The p-n heterojunctions abtained on n-Si and p-Si ware measured for their resistance value and I-V curve. For resistance measurement, n type doping material conductivity had the obvious improvement; For electrical performance measurement of p-n junction, ZnO p-n heterojunction appeared typical rectifying curve, and in contrast, p-Si /ZnO :(Al) has better electrical properties than ZnO:(Ag, N) / n-Si junctions; We determine the p-n junction rectifying curve under annealing temperatures of 600℃, and we found that annealing samples can obtain better electrical performance, and the optimum annealing temperature also requires us to further explore. |
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