| Wurtizitic ZnO is a direct wide-band gap(3.36 eV at 300 K)semiconductor with many applications,whose best photoelectronic properties have gained itself substantial interest from all over the world in the past ten years.At room temperature,it has a large exciton binding energy of 60 meV and a hexagonal wurtzite structure.Its lattice parameters are a=0.3249 nm and c= 0.5206 nm.Traditionally,Zinc oxide is a piezoelectric material which has a reasonably large piezoelectric coefficient.but since 1990s,ZnO has been researched as a photoelectric material,at the same time ZnO nanomaterials' research has also achieved vigorous development simultaneously.Acoustoelectric devices,such as surface acoustic wave devices(SAW)have been fabricated with ZnO.Due to its unique conducting mechanism based on oxygen vacancies, zinc oxide is also used in oxygen gas sensors.Furthermore,like indium oxide and tin oxide,ZnO is both transparent in the visible region and electrically conductive with appropriate dopants such as aluminum,this unique property has been widely studied for transparent conducting electrodes for flat panel displays,and solar cells.Compared with other wide-band-gap semiconductors, ZnO has many advantages,and the progress of ZnO research must be able to solve the bottleneck problems of semiconductors LEDs and LDs.In this paper,we used the magnetron sputtering technology and the hot annealing technology to fabricate the ZnO,Au nanofilms and Au nano spots on Si(111)substrates.Based on the fabricated ZnO,Au nanofilms and Au nano spots,we adopted a hot-oxidation process with a evaporated Zn source to prepare many kinds of ZnO nanostructures on many kinds of substrates, and we studied the structure,composition,morphology and optical properties of the as-prepared ZnO nanostructures,the optical mechanism and growth mechanism of GaN nanostructure are also firstly explored. Finaly,we investigate the effect of annealing temperature and time on the morphologies of the as-prepared ZnO nanostructures.All the results are as follows:1.We prepared the ZnO,Au nanofilms and Au nano spots on Si(111)substrates by the magnetron sputtering technology and the hot annealing technology.We discovered that the ZnO, Au films were affected by the sputtering film thickness,the annealing temperature and the annealing time,and prepared the well arranged Au nanospots lattices.This ZnO,Au films and the Au nanospots lattice played a vital role in the growth of ZnO nanostructures.2.We adopted a hot-oxidation process with a evaporated Zn source to prepare many kinds of ZnO nanostructures on many kinds of substrates,such as Si(111)substrates,Si based ZnO films,Si based Au films,Si based Au nanospots and quartz sbustrates.In the nanostructure growth experiment,ZnO nanorods,nanowires,nanoflowers,nanosheets and nano-tetrapods were prepared.3.Optical properties of GaN nanostructures.For the optical property,the measurement of PL spectrum was performed with a Xe lamp as the excitation source(wavelength was 325 nm)at room temperature.There are two peaks located at 386nm,505nm,respectively.The peak located at 386 nm correspond to the near-band-adge emission,which usually ascribed to the near-band-edge exciton transition。The peak located at 505nm is referred to as a deep-level or trap-state emission. Vanheusden et al.attributed the green emission to a singly ionized oxygen vacancy in ZnO and suggested that the emission comes from the radioactive recombination of a photon-generated hole with an electron occupying the oxygen vacancy.4.At last we discussed the growth mechanism of each kind of ZnO nanostructures through the nanostructures' growth process and the test results' analysis.We have studied the different influence mechanism on the ZnO nanostructures growth of the growth atmosphere,the temperature,the time,the carrier gas speed of flow as well as the substrates.We summarized each kind of factor that influenced the ZnO nanostructure growth,and induced the main factors that affect the ZnO nanostructures' growth process.
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