Photon Scanning Tuneling Microscope Conbined With Artomic Force Microscope Prototype

A general trend of Scanning Probe Microscope (SPM) is to multiple functionality and digitalization. Atomic Force / Photon Scanning Tunneling Microscope (AF/ PSTM) is such a new type SPM instrument that combines the advantages of both Atomic Force Microscope (AFM) and Photon Scanning Tunneling Microscope (PSTM). By the using of AF/PSTM dual-functional bend optical fiber tip, AF/PSTM works at resonant modulation imaging mode, and gets two AFM images (topography and phase image) and two PSTM images (transmissivity and refractive index image) of sample simultaneously in once scanning.General (with single beam) PSTM has two difficulties at imaging, that one is the artifact false image in optical image another is the mixture of topography with optical image. Basing on the professor Wu 's thesis on separating image method of AF/PSTM, author applied an item from National Science Youngest Fund on "photon scanning tunneling microscope (PSTM) tip resonance modulation imaging mode", which is the opening report of doctorial thesis. With supports of national fund and DLUT fund, this thesis title was extended to development of the functional prototype of new type AF/PSTM.In the first chapter of this doctorial thesis, the international development status of the Scanning Probe Microscope is introduced. The principles of AFM, PSTM and SNOM are described and as an important part the problems of PSTM are indicated.Second chapter, shows the basic theories of AF/PSTM including the theory on reducing PSTM optical artifact false image and theory on separating optical signal of PSTM. Basing on those theories, AF/PSTM dual-functions bend optical fiber tip shows that AF/PSTM how can get the transmissivity, refractive index image, topography and phase image of sample working at resonant modulation constant amplitude imaging mode. Then the schematic of AF/PSTM is formed and the whole system structure design is found.The third chapter inherits the second chapter's request of design of AF/PSTM, describing how to develop AF/PSTM., in this part, the main works include: resolving resonance scanning mode with dual-functional optical fiber, designing principal-minor structure, real-time separating PSTM optical image signal, designing main instrument box, and searching resonance peak. The principal-minor structure could support hardware upgrading, and being close to commercial prototype instrument.The fourth chapter introduces the development of AF/PSTM host software. The monitor module manages the whole system, including the user interface, DSP card and main instrument box. The software is a WINDOWS application programmer, which bases on many modules. And the data files are compatible with DI Company of USA.The fifth chapter introduces the design of DSP card and DSP software.