Particular artifacts of topographic images of dielectrics in atomic-force microscopy

Development of an improved Kelvin probe force microscope for accurate local potential measurements on biased electronic devices

“…As the measured topography profile is related to the total tip-sample interaction force, any additional force component, such as the electrostatic interactions due to the sample charges present in a biased device, will alter the measurements (Girard, 2001;Belaidi et al, 1997). Artefacts in AFM topography image are therefore present over the sample charged regions due to sample biasing both for tapping mode (Dianoux et al, 2003;Yan & Bernstein, 2006;Tolstikhina et al, 2007) and noncontact mode (Shiota & Nakayama, 2001;Sadewasser & Lux-Steiner, 2003) measurements. Although in the electrostatic force microscopy (EFM) these artefacts are used for charge detection (Belaidi et al, 1997;Girard, 2001), in KPFM-AM, they will induce errors in the surface potential measurements for both lift mode and dual-frequency mode.…”