Apparent height in tapping mode of electrostatic force microscopy

We investigate a source of error in electrostatic force microscopy (EFM) measurements. During EFM, the probe performs two scans: the first to obtain the topography in tapping mode and the second at a chosen lift height to measure the electrostatic force. However, during the first scan, the electrostatic force between the probe and sample can cause error in the height measurement. In this work, micron-sized wires are fabricated, and test voltages applied. Experiments demonstrate that attractive electrostatic forces result in erroneous height measurements. A tip–sample interaction model is provided.