Object size effect on the contact potential difference measured by scanning Kelvin probe method

Abstract

and macroscopic Kelvin probe are close within the error of about 10-30% for large studied objects, whereas scanning Kelvin probe microscope signal decreases, when the object size becomes smaller than 1.4 µm. CPD and electric field signals measured using many-pass technique allowed us to estimate the influence of electrostatic field disturbance, especially, in the case of small objects.

Three‐Dimensional Kelvin Probe Microscopy for Characterizing In‐Plane Piezoelectric Potential of Laterally Deflected ZnO Micro‐/Nanowires

“…The oscillating potential difference between the tip and surface results in an oscillating electrostatic force of the form where K ( z ) and V ( z ) are the tip‐surface capacitive coupling and potential, respectively. The capacitive coupling K ( z ) has been shown to depend on tip, cantilever, and surface geometry, as well as average tip‐surface distance z 31–41. Note that K ( z ) determines the form of the point spread function with which V ( z ) is convolved to produce an SKPM image 32, 37, 40, 42–44.…”

“…The capacitive coupling K ( z ) has been shown to depend on tip, cantilever, and surface geometry, as well as average tip‐surface distance z 31–41. Note that K ( z ) determines the form of the point spread function with which V ( z ) is convolved to produce an SKPM image 32, 37, 40, 42–44. While deconvolution processes are required for truly quantitative measurement of surface potential, we neglect this consideration at present to focus on applicability of 3DKPM to high‐topography surfaces.…”

“…In practice, however, there typically exists a nonzero tracking error in the V DC feedback loop,39, 45 introducing error as V DC = ( V ( z ) + V error ). The magnitude of V error increases when V ( z ) changes rapidly, such as with discontinuities in V abs or ( χ tip –χ s ) at ferroelectric domain boundaries, monolayer growth step edges, and metal‐semiconductor junctions 30, 32, 34–38, 45. Furthermore, the finite response time of the feedback loop holding z constant has a nonzero tracking error, introducing additional error as V DC = [ V ( z + z error ) + V error ] if there are variations in topography of the surface.…”

Small-Area Techniques for Micro- and Nanoelectrochemical Characterization: A Review

“… a SKP, scanning Kelvin probe; SKPFM, scanning Kelvin probe force microscopy. Information compiled from refs and − . More details of the advantages and disadvantages of different AFM modes can be found in refs and .…”