Investigation Of Fabrication And Synthesis Of ZnO Nanostructures On Si Substrates

Nanomaterials have gained itself substantial interest from all over the world and become an hot spot in the area of nanotechnology because of its best photoelectronic properties, chemical and mechanical performance. The research on nanomaterials science includes structures, performances, applications as well as preparation and examination methods of nanomaterials. During its developing process, the nanomaterials science and technology converges gradually with other subjects, and has developed into some new subjects and domains with much more potentials, such as nanoelectronics, nano chemistry, nano biology, nanomolecular electronics and nano electronic devices, etc.Wurtizitic ZnO is a direct wide-band gap(3.36eV at 300K) semiconductor with many applications,whose best photoelectronic properties have gained itself substantial interest from all over the world in the past ten years. 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. ZnO is an a II-VI compound direct wide-band gap semiconductor, whose excition binding energy is as high as 60meV. In ordinary circumstances, ZnO contains a wurtizitic structure, and its crystal constant a = 0.3249nm, c = 0.5206nm. The traditional use of ZnO is a kind of piezocrystal with a high piezo-electric modulus, but since 1990s, ZnO has been researched as a photoelectric material, and ZnO nanomaterials' research has also achieved vigorous development simultaneously. This research mainly includes two aspects, firstly 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 wet-oxidation process with a evaporated Zn source to prepare many kinds of ZnO nanostructures on many kinds of substrates, and we tested and studied the structures, compositions, morphologies by many kinds of electronic microscopes, X-ray diffraction and so on. Analyzing the growth process of ZnO nanostructures and the results of test, we also carried on a iscussion to the ZnO nanometer structures'growth mechanism. The primary contents 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) On the foundation of prepared ZnO, Au nanofilms, we, we adopted a wet-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) We carried on many equipments and technologies, such as SEM, TEM, HRTEM, XRD, AFM, SAED etc. to test and characterize the as-prepared nanostructure samples of ZnO.(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.