Scanning Tunneling Microscopy STM

Developed by G. Binnig and H. Rohrer in 1981, Scanning Tunneling Microscopy (STM) is a groundbreaking technique used to capture high-resolution images of surfaces at the atomic scale. Designated as the “microscope of the 21st century,” STM has revolutionized materials science and nanotechnology fields.

Key Principles of STM

The STM’s operational principle hinges on the quantum mechanical phenomenon known as “quantum tunneling.” A sharp metallic probe is positioned in close proximity to the sample’s surface. When a voltage is applied, electrons can “tunnel” through the vacuum barrier between the probe and the sample’s surface. The amount of tunneling current that flows is directly proportional to the distance between the probe and the surface, enabling the creation of a detailed topographic map of the sample.

STM’s Versatility and Applications

STM’s versatility extends across various scientific disciplines. Some of its key applications include:

  • Imaging the arrangement of atoms and molecules on surfaces
  • Studying the electronic structure of materials
  • li>Analyzing biological samples at high resolution

  • Developing novel materials and nanostructures.

Advantages of STM over Other Methods

STM offers several advantages over other microscopy techniques:

  • Atomic-scale resolution
  • Non-destructive nature of imaging
  • Ability to image both conducting and non-conducting materials
  • Variety of sample types that can be analyzed

Conclusion

STM is a powerful microscopy tool that has transformed our understanding of materials at the atomic level. Its versatility and ability to provide unprecedented resolution have made it an indispensable tool for scientists and engineers in various disciplines.