STM and Related Techniques
Resolution: STM is capable of imaging individual atoms on a surface. There are few other techniques that provide similar resolution, showing single atoms only under very particular conditions. In field ion microscopy, for instance, only atoms located at the apex of the field-emission tip can be imaged individually.
New information: Tunnel electrons arrive at the sample surface with millivolt to few-volt energies. They gently stroke the surface instead of striking it like in a conventional electron microscope. As a consequence STM provides preferentially information on the most softly bound electrons — the electrons near the Fermi level, which happen to be the most important for many chemical and electrical properties and processes. Furthermore, having such a small energy, object damage due to electron irradiation is practically impossible. This can be important for the study of low-stability materials such as biological tissue.
New approach: The STM as an instrument has more in common with a profilometer than with a conventional microscope. In any conventional microscope, a beam of particles/waves is directed onto or emitted from the surface, creating an image by diffraction, deflection, or projection. In STM, a stylus of finite, actually huge mass (compared to the structures to be analyzed) is physically moved across the surface — a few years ago, probably no one would have expected that such a scheme could be used successfully to obtain atomic resolution.
Nano-engineering: The surprising results of STM indicate a possibility to manipulate macroscopic bodies with atomic precision. As we are penetrating deeper into the world of nanometer dimensions — be it in microelectronics, be it in biology — such a capability is of utmost interest not only for surface characterization but also for modification, processing and alignment on the mesoscopic, say, 0.3 to 30 nm scale.
KeywordsTunnel Current Atomic Resolution Silver Surface American Physical Society Jellium Model
Unable to display preview. Download preview PDF.
- 1.G. Binnig and H. Rohrer, Physica 127B, 37 (1984).Google Scholar
- 4.b)U. Köhler, R. J. Hamers and J. E. Demuth (in prep.).Google Scholar
- 7.R. Christoph, H. Siegenthaler, H. Rohrer and H. Wiese, Electrochimica Acta (to be publ.).Google Scholar
- 8.B. Michel and G. Travaglini, Proc. 1988 STM Conf., Oxford: J. Microsc. (in press).Google Scholar
- 12.J. H. Coombs, J. K. Gimzewski, B. Reihl, J. K. Sass and R. R. Schlittler, Proc. 1988 STM Conf., Oxford: J. Microsc. (in press).Google Scholar
- 14.B. Persson and A. Baratoff (in prep.).Google Scholar
- 15.J. H. Coombs and J. K. Gimzewski, Proc. 1988 STM Conf., Oxford: J. Microsc. (in press).Google Scholar
- 16.U. Dürig, O. Züger and D. W. Pohl, Proc. 1988 STM Conf., Oxford: J. Microsc. 152, pt. I, 259 (1988). U. Dürig, J. K. Gimzewski and D. W. Pohl, Phys. Rev. Lett. 57, 2403 (1986).Google Scholar
- 17.M. Nonnenmacher, J. W. Bartha, O. Wolter, D. W. Pohl and R. Kassing, Beitr. Elektronenmikr. Direktabb. Oberfl. 21, 13 (1988).Google Scholar
- 21.for a recent review see D. W. Pohl, U. Ch. Fischer and U. T. Dürig, Proc. SPIE 897, 84 (1988).Google Scholar
- 22.a)D. W. Pohl, W. Denk and U. Dürig, Proc. SPIE 565, 56 (Micron and Submicron Integrated Circuit Metrology 1985)Google Scholar
- 23.E. Betzig, M. Isaacson, H. Barshatzky, A. Lewis and K. Lin, Proc. SPIE 897, 91 (1988).Google Scholar
- 24.U. Ch. Fischer, U. T. Dürig and D. W. Pohl, Appl. Phys. Lett. 52, 249 (1988).Google Scholar
- 31.H. P. Kleinknecht, H. Meier and J. Sandercock, Beitr. Elektronenmikr. Direktabb. Oberfl. 21, 19 (1988).Google Scholar
- 32.H. K. Wickramasinghe (priv. communic.).Google Scholar
- 34.P. Hansma, Proc. 1988 STM Conf., Oxford: J. Microsc. (in press).Google Scholar