Measurement of local electrical conductivity by four-point probe atomic force microscope technique

Development of an atomic force microscope (AFM) probe for local electrical conductivity measurement is reviewed. Electrical conductivity of a 99.999% aluminum wire having a 400nm width and a 350nm thickness was measured by the four-point (4P) AFM probe. This technique is a combination of the principles of the four-point-probe method and standard AFM. The instrument is capable of simultaneously measuring both surface topography and local conductivity. The repeatability of conductivity measurements indicates that this 4P-AFM probe could be used for fast in situ characterization of local electrical properties of nanocircuits and nanodevices.