| In this dissertation, by using implantation of metal ions into three kinds ofsubstrates, i.e. SiO2,α-Al2O3 and Si (100), the fabrication of NPs, their thermalevolution as well as their optical properties have been studied through a series ofanalytical techniques, including Ultra-violet-visible optical spectroscopy (UV-Vis),X-ray diffraction spectroscopy (XRD), cross-sectional transmission electronmicroscopy (XTEM), atomic force microscopy (AFM) and photoluminescence (PL).The main research contents and the corresponding results are given as follows:(1) SiO2 samples were implanted with 45 keV Zn ions at fluences ranging from5×1015 to 1.0×1017 ions/cm2. The formation of Zn NPs has been systematically studiedas a function of ion fluence. The strongest surface plasmon resonance (SPR) peak hasbeen found in the 5×1016 ions/ cm2 Zn ion implanted sample. While at temperature of600°C, Zn nanoparticles could be thoroughly transformed into ZnO NPs. As thetemperature reaches at 700°C, the ZnO could be partially transformed into Zn2SiO4NPs.(2) SiO2 samples were implanted with 45 keV Zn ions at fluence of 5.0×1016ions/cm2, and were then subjected to thermal annealing in different atmospheres, i.e.oxygen, nitrogen and sequentially annealed in nitrogen and oxygen atmospheres,respectively. ZnO NPs have been effectively formed with preferred (002) and (103)orientations when the samples were annealed in oxygen ambient or in a combinationof nitrogen and oxygen ambient. The photoluminescence (PL) measurements clearlyshow that high quality ZnO NPs could be formed when the samples were sequentiallyannealed in the flow of nitrogen and oxygen gas. However, annealing in nitrogenambient only induce the growth of the Zn NPs.(3) the Zn implanted SiO2 was irradiated by post 2×016 ions/cm2, 500 keV Xeions.Uniform and spherical ZnO nanoparticles (NPs) have been created in SiO2 by Znion implantation and post Xe ion irradiation combined with annealing in oxygenatmosphere at 600°C. Irregularly shaped ZnO NPs with a broad size distribution of 5-30 nmhave been tailored to spherical shape with a narrow size distribution of 3-5 nm.Rutherfordbackscattering (RBS) measurement results show that the post Xe irradiation causes abroad profile of Zn atoms with nearly homogeneous concentration, which is mainlyresponsible for the formation of ZnO with a narrow size distribution as well as the reduction in their sizes.(4) Fabrication and evolution of Cu NPs have been investigated in1.0×1017ions/cm2, 45 keV Cu ion implantedα-Al2O3 under annealing in vacuum oroxygen atmosphere. The evolution of the Cu NPs has been found to depend stronglyon annealing atmosphere in the temperature of 300-600 oC. Annealing in vacuum onlygives rise to a slight change in the sizes of Cu NPs. However, annealing in oxygenambient not only promotes the growth of Cu NPs, but also leads to formation of CuONPs at 600oC due to the interaction of Cu NPs with O2.(5) Using implantation of 45 keV Zn ions intoα-Al2O3 at a fluence of1.0×1017ions/cm2, the effects of implant-induced defects and formation of NPs onoptical properties of substrate have been studied. Our results reveal that Zn ionimplantation could generate the F- type defects in the Al2O3, which result in the strongdefect emission. After 600oC annealing, the intensity of PL emission has been foundto increase remarkably, owing to the overlapping of the ZnO emission and theemission induced by defects in Al2O3.(6) Si(100) wafers were implanted with 45 keV Zn ions at fluence of1.0×1017ions/cm2. Our results clearly show Zn NPs could be formed in theas-implanted sample. During annealing in oxygen ambient, it has been found that theZn NPs begin be oxidized at 400oC. After 600°C annealing, most of the Zn NPs areoxidized to ZnO and they show a (101) preferential orientation. XTEM observationsindicate that the formed ZnO NPs have sizes in the range of 2-7 nm with a mean size ofabout 3.4 nm.
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