Scanning Tunneling Microscope (STM) and Atomic Force Microscope (AFM)

A scanning tunneling microscope (STM) is a type of scanning probe microscope used for imaging surfaces at the atomic level. STM is based on the concept of quantum tunneling. When the tip is brought very near to the surface to be examined, a bias voltage applied between the two allows electrons to tunnel through the vacuum separating them. The resulting tunneling current is a function of the tip position, applied voltage, and the local density of states (LDOS) of the sample. Information is acquired by monitoring the current as the tip scans across the surface, and is usually displayed in image form.

An atomic force microscope (AFM) is a type of scanning probe microscope whose primary roles include measuring properties such as magnetism, height, friction. The resolution is measured in a nanometer, which is much more accurate and effective than the optical diffraction limit. It uses a probe for measuring and collection of data involves touching the surface that has the probe. An image is formed when the scanning probe microscope raster-scans the probe over a section of the sample, measuring its local properties concurrently.

CETC is a premier provider of scanning tunneling microscopy and atomic force microscopy systems, catering to the demands of scientific research, the nanotechnology industry, semiconductor production, and quality control.