Scanning tunneling microscope (STM)

The scanning tunneling microscope (STM) is an advanced technique in surface technology that makes it possible to image surfaces at the atomic level. In contrast to conventional optical microscopes, the STM does not work with visible light, but uses quantum mechanical effects to create high-resolution topographical images of surfaces.

The way the scanning tunneling microscope works is based on the quantum mechanical tunnel effect. A fine metal tip is positioned at an extremely small distance from the sample surface. Electrons can tunnel quantum mechanically through the vacuum gap between the tip and the sample if a certain distance is maintained. The tunneling current created by this process is measured and serves as the basis for generating high-resolution topographical maps of the surface.

The extraordinary spatial resolution of the STM enables the visualization of atomic and molecular structures on surfaces. This capability makes the STM a crucial tool in materials research and nanotechnology. It is often used to characterize the surface properties of materials and to track changes at the atomic level.

The scanning tunnelling microscope also has applications in the semiconductor industry, where it is used to characterize surface structures on micro- and nanoscales. The precise control and imaging at the atomic level make the STM an indispensable tool for scientists and engineers who want to examine and manipulate surfaces at the smallest scale.