atomic force microscope

(redirected from AFM in Bio)
Also found in: Dictionary.

atomic force microscope

atomic force microscope (AFM), device that uses a spring-mounted probe to image individual atoms on the surface of a material, first developed by Gerd Binnig in 1986. Unlike the scanning tunneling microscope, which is also a scanning probe microscope, the AFM can be used on materials that do not conduct electricity. In the original AFM, the probe traverses the surface, moving upward due to bumps and downward due to depressions; a laser beam reflected from the tip of the probe measures the up and down movements, and the pattern of reflected light creates an image of the surface. Another type of AFM measures the sideways deflection of the tip caused by friction as the probe moves across the surface; differences in friction can be used distinguish different atoms and molecules on the material. A third variation employs a magnetic probe; this probe does not touch the material but moves up and down in reaction to the magnetic forces between the tip and the surface. In a microchip-size AFM, the electronic circuitry and multiple probes are integrated on a sliver of silicon; although less sensitive than a full-size AFM, the device has applications in microelectronics where the multiple probes make it possible to record images very quickly.
The Columbia Electronic Encyclopedia™ Copyright © 2022, Columbia University Press. Licensed from Columbia University Press. All rights reserved.

atomic force microscope

[ə¦täm·ik ¦fȯrs ′mī¦krə‚skōp]
(engineering)
A device for mapping surface atomic structure by measuring the force acting on the tip of a sharply pointed wire or other object that is moved over the surface.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

AFM

(Atomic Force Microscope) A device used to image materials at the atomic level. AFMs are used to solve processing and materials problems in electronics, telecom, biology and other high-tech industries. Invented by IBM in 1986, it uses a ceramic or semiconductor tip one atom wide positioned at the end of a cantilevered bar. As the tip is moved over the material, it either continously touches or periodically taps the surface and bends as it is repelled or attracted to the structure. A laser picks up the deflections.

In contrast to a scanning tunneling microscope (STM), which sends current to the surface being measured, AFMs can be used to image non-conductive materials. See probe storage, STM, microscopy and nanotechnology.
Copyright © 1981-2019 by The Computer Language Company Inc. All Rights reserved. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction is strictly prohibited without permission from the publisher.