The conductivity of the sample can be measured while scanning in contact mode by using a current amplifier to measure current flow between a conductive tip and an electrically-biased sample. Regions of high conductivity on the sample surface allow current to pass through easily, while regions of low conductivity will have a lower current due to local changes in resistance. In addition, detailed electrical properties of the surface at a specific point can be measured, which is called I-V Spectroscopy. A plot of the measured tip current (I) as a function of the applied bias voltage (V) reveals current-voltage behavior at individual contact points of a sample. Conductive AFM yields both the topography and the current map of a sample surface simultaneously.

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