Kelvin probe force microscopy on InAs thin films grown on GaAs giant step structures formed on (110) GaAs vicinal substrates

Surface potential measurements on InAs thin films grown on GaAs giant steps were performed by Kelvin probe force microscopy. We found that the removal of the water-related layer from both surfaces on a sample and a tip was very effective to improve the reliability of the surface potential measurements. The measured potential distribution corresponds to the surface corrugation of the InAs thin films. In addition, the InAs layer thickness dependence of the surface InAs Fermi levels is investigated, indicating that the surface Fermi level shifts toward the vacuum level as the increase of the InAs layer thickness. (C) 2001 American Institute of Physics.