# Fileset

[s-info1.pdf](https://mdr.nims.go.jp/filesets/e40be11d-ee13-4639-878f-07bd80afdbac/download)

## Creator

[Nobuyuki Ishida](https://orcid.org/0000-0003-0161-0583), [Takaaki Mano](https://orcid.org/0000-0002-6955-260X)

## Rights

This is the version of the article before peer review or editing, as submitted by an author to Nanotechnology .  IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it.  The Version of Record is available online at https://doi.org/10.1088/1361-6528/ad0b5e.[In Copyright](http://rightsstatements.org/vocab/InC/1.0/)

## Other metadata

[Quantitative characterization of built-in potential profile across GaAs p–n junctions using Kelvin probe force microscopy with qPlus sensor AFM](https://mdr.nims.go.jp/datasets/2c3884a5-3f26-4d78-9d44-5a6792738065)

## Fulltext

Supplementary information:Quantitative characterization of built-in potential profile acrossGaAs p-n junctions using Kelvin probe force microscopy withqPlus sensor AFMNobuyuki Ishida1 and Takaaki Mano11National Institute for Materials Science,1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan1(a) (b)-2.0 -1.0 0.0 1.0 2.0Bias voltage (V)-2.0 -1.0 0.0 1.0 2.0Bias voltage (V)-0.3-0.8 -0.8-1.0-0.9-0.6 -0.6-0.7-0.4 -0.4-0.5-0.2 -0.2Frequency shift (Hz)Frequency shift (Hz)2nd-order poly. fit9th-order poly. fitExperiment2nd-order poly. fit9th-order poly. fitExperimentFIG. S1: ∆f–U spectra obtained at (a) n- and (b) p-type regions and the fitting curves using 2nd-and 9th-order polynomials. The vertical lines indicate the inflection points of each polynomial.0 4020 80 100 14060Distance (nm)120 160 0 4020 80 100 14060Distance (nm)120 160 0 4020 80 100 14060Distance (nm)120 160 0 4020 80 100 14060Distance (nm)120 1600.00.2-0.20.4-0.40.6-0.60.81.0CPD (V)0.00.2-0.20.4-0.40.6-0.60.81.0CPD (V)2nd-order fitSimulation3rd-order fitSimulation4th-order fitSimulation5th-order fitSimulation6th-order fitSimulation7th-order fitSimulation8th-order fitSimulation9th-order fitSimulation(a) (b) (c) (d)(e) (f) (g) (h)FIG. S2: Dependence of the CPD profiles across the p-n junction on the order of the polynomialused for fitting.2-0.2 -0.1 0.0 0.1 0.2 0.3 0.4 0.5 0.6Voltage (V)4003002001000-100-200-300-400Current (mA)Dark539 mVLightFIG. S3: Current-voltage characteristics of the p-n diode obtained under dark and light-irradiationconditions. Rectification characteristics of the diode were observed. The open circuit voltagemeasured from the X-intercept of the curve was 539 mV.3-2.0 -1.00-100-200-300-4000.0 1.0 2.0Bias voltage (V)Dz (pm)-2.0 -1.00-100-200-300-4000.0 1.0 2.0Bias voltage (V)Dz (pm)Tunneling current (A)10-1010-810-1210-1410-16Tunneling current (A)10-1110-910-1310-1510-17Variable tip-sample separationECEV ECEV(a) (b)Constant tip-sample separationVariable tip-sample separationConstant tip-sample separationFIG. S4: It–U spectra obtained with the variable tip-sample separation technique and the spectraconverted to the constant tip-sample separation, obtained at (a) n-type and (b) p-type regions.The bottom graphs show the bias dependent offset of the tip-sample separation (∆z). The offsethas the form ∆z(U) = a|U | where U is the bias voltage. Proportionality coefficient, a, was180 pm/V for both positive and negative bias voltage. The vertical dashed lines indicate thetheoretical positions of the band edges. The onset of the conduction (valence) band componentfor the n-type (p-type) region coincided well with the position of EC (EV ). In contrast, the onsetof the valence (conduction) band component in the n-type (p-type) layer deviated slightly fromthe band edges by 50-100 mV. This small deviation was induced by the relatively small currentcomponent, called dopant-induced component (D-component) observed in the band gap region.The valence (conduction) band component in the n-type (p-type) layer began to appear only whenthese components became larger than the D-component. Thus, the apparent onsets shifted fromthe actual positions. The onset position for the n-type layer was not clear due to the relativelylarge D-component.4