Study Of The Highly Charged Ion Interaction With Solid Surface

Highly Charged Ion (HCI) is the ion in high charge state, which is produced by the loss of most or all of the atom's bounded electrons. The most outstanding feature is the great amount of potential energy carried by HCI. The study on the interaction of HCI and material attracts great interests in astrophysics, atomic physics, radiation biology, nano-material and the design of fusion reactor. Due to the unique property of HCI, it has the very special application in surface analysis and surface modification at the nanoscale, thus the HCI has been expected as a new generation tool for the microelectronic engineering. Additionally, HCI is the favorite candidate in medical application of heavy ion cancer therapy since the special interaction between the well-accelerated HCI and organics.In this thesis, we introduced:the special properties of HCI; the HCI source facilities e.g. Electron Cyclotron Resonance Ion Source (ECRIS) and Electron Beam Ion Trap (EBIT); as well as the proposed theory models and the experimental results in this study field. In our work, the studies of sputtering produced by HCI interaction with various solid surfaces were reported first. The work about hillock-like nanodefect induced by bombardment of HCI on mica surface was also introduced. Last, the investigation on the diamond-like carbon production by impacting of HCI on HOPG surface was presented.On the study of sputtering induced by HCI, the highly charged Arq+(q=1～16), Pbq+(q=4-36) ions with various kinetic energies were employed to impact on the kinds of targets, including the metals:gold (Au), copper (Cu), aluminum (Al), niobium (Nb), molybdenum (Mo), tantalum (Ta); the semiconductor:N-type silicon (Si); the insulator:silicon dioxide (SiO2). Using a MCP detector, the sputtered particles (part of sputtered atoms and positive secondary ions) yields were recorded and the results were presented:1. the dependency of sputtering yield on incident angle; 2. the correlation between sputtering yield and charge state (potential energy), and the sputtering results varied on different targets; 3. kinetic sputtering yield was related to the nuclear stopping power at the surface, however the energy loss at the surface was found to be enhanced by the charge state on the Mo and Ta targets, respectively; 4. the potential sputtering on different materials were systematically discussed. And we found the potential sputtering phenomenon was incidental on semiconductor and insulator surfaces, but for some metal targets, only the potential energy surpassed the threshold value, the potential sputtering becomes realizing. Additionally, based on the proposed models and the properties of material, an assumption which describes the electronic excitation distribution on surface produced by the HCI approach is made. And according to our results the possible roles of these electronic excitations for potential sputtering were discussed.AFM was chosen to observe the hillock-like nanodefects induced by the bombardment of highly charged Xeq+ion on mica surface. The diameter/height of the nanodefect relates to both the potential and kinetic energy. The number of displaced target atoms during the nanodefects formation was estimated. The latest experimental results on the HCI-produced nanodefect study were introduced too.With employing the Xeq+to impact on Highly Oriented Pyrolytic Graphite (HOPG) surface, the surface structure transition from sp2 to sp3 hybridization was shown by the Raman spectroscope and XPS results as well, which proved the diamond-like carbon production on graphite with HCI irradiation. The ratio ofⅠ(sp3)/Ⅰ(sp2) was found to increase with potential energy, and it was saturated when the fluence of ions increased higher than a critical value. Moreover, theⅠ(sp3)/Ⅰ(sp2) ratio was inversely proportional to the kinetic energy, and the amount of potential energy deposited onto the surface local area increased with decreasing of kinetic energy.