Kelvin probe force Microscopy is based on minimization of the electrostatic force between conductive AFM probe and sample by applying a voltage that compensates contact potential difference. The simplest realisation is AM-KPFM where probe is kept out of the contact to the sample, AC voltage is applied on it and DC offset is used to minimized the mechanical oscillations caused by electrostatic forces at the AC voltage frequency.

To set up the AM-KPFM operation with Gwyscope, it is necessary to mount a conductive probe into your microscope and to adjust the wiring so the AC+DC voltage from Gwyscope fast output 2 is applied between probe and sample. Then set up the probe for tapping mode operation and establish the feedback. In KPFM tabl in the main Gwyscope window, select AM-KPFM, like shown here:

When if feedback, KPFM setup window can be run and KPFM response, including various KPFM can be tuned as shown below:

AM KPFM is typically performed at the mechanical resonance frequency of the cantilever. That's why the frequency is automatically adopted from the tapping mode setup after it is selected and is helpful to set up the tapping mode first, as suggested above.

To set up the second pass measurement in which KPFM will be acquired, use the Lift tab in the main Gwyscope window. In the image below, 100 nm lift was chosen. In every profile, the topography is measured first and then the profile data are shifted by 100 nm and another scan is performed, with AM KPFM feedback on.