Scanning voltage microscopy (SVM) -- sometimes also called nanopotentiometry -- is a scientific experimental technique based on atomic force microscopy. A conductive probe, usually only a few nanometers wide at the tip, is placed in full contact with an operational electronic or optoelectronic sample. By connecting the probe to a high-impedance voltmeter and rastering over the sample's surface, a map of the electric potential can be acquired. SVM is generally nondestructive to the sample although some damage may occur to the sample or the probe if the pressure required to maintain good electrical contact is too high. If the input impedance of the voltmeter is sufficiently large, the SVM probe should not perturb the operation of the operational sample.

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