The Development Of Scanning Probe Electron Energy Spectrometer And Its Applications To Surface Studies

With the rapid development of surface science and the improve of surface analysis techniques, people are no longer satisfied with a little information of the sample obtained by a single analytical technique, but more hope to get complete characterization of the solid surface using a versatile analytical system. The combination of scanning tunneling microscope (STM) and electron energy spectroscopy measurement technology, named scanning probe electron energy spectrometer (SPEES) is a viable option. This thesis introduces the design principles of SPEES, construction of the instrument, and the debugging process. Furthermore, two experimental studies with SPEES are introduced respectively.In chapter1, we describe the formation and development of surface science, and introduce the wide range of applications of the special performance of the solid surface. Moreover, we show a series of solid surface analysis techniques, and point out that various techniques combined to analyze solid surface is demand. We also show some of the multi-function analysis systems in the world.Chapter2introduces all parts of the SPEES, including vacuum system, transmission system, STM, energy analyzer, detector, power supply systems and so on. Some design index of this spectrometer is also given.In chapter3, a general and simple equation for the point-to-point focusing in the radial plane of DTA has been obtained. The calculated deflection angles suing the equation are in good agreement with the trajectory simulations given by SIMION program. The equation could be quite useful for the design of DTA.In chapter4, we show the optimization process of SPEES, and all parts of the instrument run in good condition. In addition, a full spectrum of graphite from zero energy secondary electron to elastically scattered electron is obtained using scaning mode. The peaks at secondary electron region are assigned accordingly.Chapter5reports the first observation of that the intensity of inelastic electron scattering from silver nanostructures on HOPG surface increases nonlinearly with respect of the external electric field generated by the tip-sample bias. A one electron two-step model has been invoked to explain the observed phenomenon. The cause to form it is also explained by the theoretical calculation.Chapter6introduces the diffraction pattern of secondary electron excited by field emission gun between two nearest-neighbor atoms in adjacent layers.