# Fileset

[s-info1.pdf](https://mdr.nims.go.jp/filesets/1e7d56a2-12b4-403e-ae4c-32a4b9e9aa65/download)

## Creator

[Nobuyuki Ishida](https://orcid.org/0000-0003-0161-0583)

## Rights

©2025 American Physical Society[In Copyright](http://rightsstatements.org/vocab/InC/1.0/)

## Other metadata

[Influence of Fermi level pinning on contact potential difference measurements using Kelvin probe force microscopy](https://mdr.nims.go.jp/datasets/aec52709-2acb-4fe7-a0bc-9742174c369b)

## Fulltext

Supplementary information:Influence of Fermi level pinning on contact potential differencemeasurements using Kelvin probe force microscopyNobuyuki Ishida11National Institute for Materials Science,1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan1s = 1 nmRtip = 5 nmRtip = 10 nmRtip = 30 nmRtip = 60 nmRtip = 100 nmRtip = 200 nms = 5 nms = 10 nms = 30 nms = 50 nms = 100 nm(a)Electrostatic force (nN)Electrostatic force (nN)Electrostatic force (nN)Bias voltage (V)(b)(c)Rtip = 10 nms = 1.53 nms = 100 nmRtip = 100 nm0.0-3.0-20-15-10-50-2.5-2.0-1.5-1.0-0.50.0-0.6-2.0 -1.0 0.0 1.0 2.0-0.5-0.4-0.3-0.2-0.1FIG. S1: To examine the generality of the high surface sensitivity of KPFM discussed in SectionIIIA in the main article, we calculated the electrostatic force as a function of bias voltage for largertip-sample separations (s) and tip radii (Rtip) under the strong Fermi level pinning condition. In(a), the calculations were performed while keeping Rtip constant at 10 nm and varying s from 1 to100 nm. In (b), the results were obtained by keeping s constant at 1.53 nm and varying Rtip from5 to 200 nm. In (c), calculation was performed using large values for both s and Rtip (100 nmand 100 nm, respectively). The vertical dashed line indicate the values of V ∗CPD. In all cases, themagnitude of the electrostatic force and the curvature of the Felec(U) spectra exhibited significantdependence on s and Rtip. However, U∗, bias voltage at which the electrostatic force is minimized,remained nearly unchanged.2(a)(b)(c)(d)FIG. S2: To examine the generality of the results shown in Fig. 4 in the main article, we calculatedU∗ and for larger s and Rtip while varying the DOS of the surface states. (a) and (b) shows theresults obtained using s = 100 nm and Rtip = 10 nm, and (c) and (d) show the results obtainedusing s = 100 nm and Rtip = 100 nm. In (a) and (c), solid circles and triangles represent the valuesof U∗ and V ∗CPD, respectively, plotted as a function of ρss. The dashed horizontal line indicates thevalue of V ∗CPD for the pristine GaAs(110) surface. (b) and (d) show the differences between U∗ andV ∗CPD values.3