Determination of the nonlinearity of capacitive sensors along the Z-axis of an atomic force microscope

The nonlinearity of capacitive sensors along the Z-axis of an atomic force microscope is investigated using test structures containing relief elements of height 300–1200 nm. The dependence of the results of height measurements on the value of the displacement of the tubular piezoelectric scanner over a range of 10–90% of the maximum possible value is established. It is shown that the nonlinearity of displacement and direction capacitive sensors, perpendicular to the surface being investigated, is 1.5–3%.