Atomic Force Microscopy And Resarch On Application Of IPC-208B Typed AFM

The nanoscale science and technology has developed greatly in recent 20 years. Hence, as one of the most important tools in nanoscale detection and nanoscale fabrication, Atomic force microscope(AFM)is receiving ever-increasing popularity in all kinds of applications. At present, the lateral resolution and vertical resolution of general commercial AFM is 0.2nm and 0.05nm, respectively. In recent years, with the deep study on biology science, not only the structure of large molecule but also the structure of small molecule has to be involved. The scale of small molecule is about 0.5nm, so it's very difficult to characterize these structures by general commercial AFM.Chongqing University has developed the AFM.IPC-208B with high resolution, which is based on the former success of STM and merges STM and AFM into one whole. AFM.IPC-208B detects cantilever's displacement by STM. Therefore it can be used as AFM or STM. The resolution of AFM is the same as STM. Its lateral resolution is 0.1nm and vertical resolution is 0.01nm, respectively.The thesis introduced the basic theories of AFM.IPC-208B, which includes atomic forces mechanism between probe tip and sample surface, and checks deformation of cantilever, and so on. The design theory of AFM.IPC-208B is analyzed. The keys such as workbench, data acquisition and control system are described. Some researches on biochemical region are developed with AFM.IPC-208B. Detecting the molecular structure of glutathione adulterated with zinc ion, the phenomenon of former hexagonal annularity have changed hexagonal annularity was found; detecting SPA, the counter clockwise helix structure was found; detecting sheep anti human IgG,the"Y"shape of hill protruding was found; detecting target gene, the"X"shape and nano-whisker which diameter is about 1.6nm was found. Those experimental results are according with the theory analyse and show AFM's good application prospect in biochemical region. Besides, the scanning tunneling spectrum of nano-titanium dioxide has been studied by the STM function of AFM.IPC-208B. The energy value indicates that the insulator's electric character have recreived great impovement after the nanometer processing. The electric character equals or even exceeds the semiconductor. Hence, the STM can be used to detect the surface of nano-insulator with its virtue of high stability.