AFM (Atomic Force Microscopy) is very high resolution scanning probe microscopy which uses a cantilever with very sharp tip to scan through the surface of the sample. When the probe tip is brought sufficiently close to the surface of the sample and moved, due to the force in between the probe tip and the surface of the sample, the cantilever moves. The deflection of the cantilever is generally detected by a laser pointing to the upper surface of the cantilever and the reflected signal is collected by an array of photodetector. Other known methods for detecting the deflection of the cantilever is to use interferometry or capacitive sensing. An electrical detection of the deflection is also used in AFMs, where the cantilever is made of piezo-electric material and a Wheatstone bridge detects the strain in the cantilever due to the friction with the sample. But this method is not so popular as the laser deflection or the interferometry are more accurate.
Analysis and operating mode
Operating environment and standard