physica status solidi (a)
© WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Editor: Stefan Hildebrandt (Editor-in-Chief), Sabine Bahrs (Deputy Editor)
Online ISSN: 1862-6319
Back Cover: Kelvin probe force microscopy in the presence of intrinsic local electric fields (Phys. Status Solidi A 4/2011)
Kelvin probe force microscopy (KPFM) measurements are based on the injection of majority charge carriers into the sample surface region. Thus, in semiconductors the measured KPFM bias is related to the energy difference between Fermi energy and respective band gap. This relation makes KPFM the best choice when aiming at quantitative dopant profiling. In the Editor's Choice article by Baumgart et al. (pp. 777–789) the influence of the chosen electrical KPFM operation frequency is discussed. It is shown how drift and diffusion of injected charge carriers may influence the detected electrical signal in semiconducting samples with horizontal p–n junctions. KPFM measurements below the operation frequency where drift and diffusion play a role, may be used to investigate the diffusion velocity of charge carriers in doped semiconductor nanostructures with internal electric fields. In general, it is of utmost importance to investigate the sample-specific dependence on local intrinsic electric fields before attempting quantitative KPFM measurements.