Instrumentation scanning tunneling microscopy

Only recent developments in instrumentation of scanning probe microscopy, such as scanning tunneling microscopy (8) and atomic force microscopy (9), have made it possible to study friction on the nanometer and higher scales. These experiments show that the behavior on the single asperity level is different from that on the macroscopic scale. 

A technique similar to scanning tunneling microscopy employing an instrument that uses a sharply... 

On the other hand, optical microscopy, confocal microscopy, ellipsometry, scanning electron microscopy (SEM), scanning tunneling microscopy (STM), atomic force microscopy (AFM) and total internal reflection fluorescence (TIRF) are the main microscopic methods for imaging the surface structure. There are many good books and reviews on spectroscopic and chemical surface analysis methods and microscopy of surfaces description of the principles and application details of these advanced instrumental methods is beyond the scope of this book. 

If one makes one of the electrodes a metal wire with a sharp tip at the end and the other electrode a planar sample separated by vacuum space, one has the basis for both point-contact electron vacuum tuimeling spectroscopy and scanning tunneling microscopy. The latter will be discussed in more detail in the next section on instrumentation. 

See also Blood and Plasma. Clinical Analysis Glucose. DNA Sequencing. Fluorescence Overview. Forensic Sciences Drug Screening in Sport. Microscopy Techniques Electron Microscopy Scanning Electron Microscopy Atomic Force and Scanning Tunneling Microscopy. Nucleic Acids Spectroscopic Methods. Raman Spectroscopy Instrumentation. Sensors Overview. 

The student should be aware that there is another class of surface analysis instruments based on analytical microscopy, including scanning electron microscopy, transmission electron microscopy, atomic force microscopy, and scanning tunneling microscopy. A discussion of these microscopy techniques is beyond the scope of this chapter. Most industrial materials characterization laboratories will have some combination of electron spectroscopy. X-ray analysis, surface mass spectrometry, and analytical microscopy instrumentation available, depending on the needs of the industry. 

More detailed surface features and topography can be revealed by scanning tunneling microscopy (STM) or atomic force microscopy (AFM). The instruments employing these techniques are capable of resolution at the atomic level. Recent efforts have also shown the feasibility of manipulating and rearranging atoms on the surface. The techniques do not require vacuum and can even be used in solution to study such processes as reactions taking place at the surfaces of electrodes, corrosion, or precipitation/dissolution phenomena. 

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