In SGM one measures the sample's electrical conductance as a function of tip position and tip potential. This is in contrast to other microscopy techniques where the tip is used as a sensor, e.g., for forces.

SGMs were developed in the late 1990s from atomic force microscopes. Most importantly, these had to be adapted for use at low temperatures, often 4 kelvins or less, as the samples under study do not work at higher temperatures. Today an estimated number of eleven research groups worldwide use the technique.