Beyond the blur: using experimentally determined point spread functions to improve scanning Kelvin probe imaging (2404.03593v4)
Abstract: Scanning Kelvin probe microscopy (SKPM) is a powerful technique for investigating the electrostatic properties of material surfaces, enabling the imaging of variations in work function, topology, surface charge density, or combinations thereof. Regardless of the underlying signal source, SKPM results in a voltage image which is spatially distorted due to the finite size of the probe, long-range electrostatic interactions, mechanical and electrical noise, and the finite response time of the electronics. In order to recover the underlying signal, it is necessary to deconvolve the measurement with an appropriate point spread function (PSF) that accounts the aforementioned distortions, but determining this PSF is difficult. Here we describe how such PSFs can be determined experimentally, and show how they can be used to recover the underlying information of interest. We first consider the physical principles that enable SKPM, and discuss how these affect the system PSF. We then show how one can experimentally measure PSFs by looking at well defined features, and that these compare well to simulated PSFs, provided scans are performed extremely slowly and carefully. Next, we work at realistic scan speeds, and show that the idealised PSFs fail to capture temporal distortions in the scan direction. While simulating PSFs for these situations would be quite challenging, we show that measuring PSFs with similar scan conditions works well. Our approach clarifies the basic principles of and inherent challenges to SKPM measurements, and gives practical methods to improve results
- W. A. Zisman, “A new method of measuring contact potential differences in metals,” Rev. Sci. Instrum. 3, 367–370 (1932).
- P. P. Craig and V. Radeka, “Stress Dependence of Contact Potential: The ac Kelvin Method,” Rev. Sci. Instrum. 41, 258–264 (1970).
- A. Nazarov and D. Thierry, “Application of Scanning Kelvin Probe in the Study of Protective Paints,” Front. Mater. 6, 462587 (2019).
- A. Nazarov, M.-G. Olivier, and D. Thierry, “SKP and FT-IR microscopy study of the paint corrosion de-adhesion from the surface of galvanized steel,” Progress in Organic Coatings 74, 356–364 (2012), application of Electrochemical Techniques to Organic Coatings.
- H. T. Baytekin, A. Z. Patashinski, M. Branicki, B. Baytekin, S. Soh, and B. A. Grzybowski, “The Mosaic of Surface Charge in Contact Electrification,” Science 333, 308–312 (2011).
- X. Bai, A. Riet, S. Xu, D. J. Lacks, and H. Wang, “Experimental and Simulation Investigation of the Nanoscale Charge Diffusion Process on a Dielectric Surface: Effects of Relative Humidity,” J. Phys. Chem. C 125, 11677–11686 (2021).
- T. Hackl, G. Schitter, and P. Mesquida, “AC Kelvin Probe Force Microscopy Enables Charge Mapping in Water,” ACS Nano 16, 17982–17990 (2022).
- Ørjan G. Martinsen and A. Heiskanen, “Chapter 7 - electrodes,” in Bioimpedance and Bioelectricity Basics (Fourth Edition), edited by Ørjan G. Martinsen and A. Heiskanen (Academic Press, Oxford, 2023) fourth edition ed., pp. 175–248.
- M. Nonnenmacher, M. P. O’Boyle, and H. K. Wickramasinghe, “Kelvin probe force microscopy,” Appl. Phys. Lett. 58, 2921–2923 (1991).
- T. Glatzel, U. Gysin, and E. Meyer, “Kelvin probe force microscopy for material characterization,” Microscopy 71, i165–i173 (2022).
- W. Melitz, J. Shen, A. C. Kummel, and S. Lee, “Kelvin probe force microscopy and its application,” Surf. Sci. Rep. 66, 1–27 (2011).
- G. Cohen, E. Halpern, S. U. Nanayakkara, J. M. Luther, C. Held, R. Bennewitz, A. Boag, and Y. Rosenwaks, “Reconstruction of surface potential from Kelvin probe force microscopy images,” Nanotechnology 24, 295702 (2013).
- T. Machleidt, E. Sparrer, D. Kapusi, and K.-H. Franke, “Deconvolution of Kelvin probe force microscopy measurements—methodology and application,” Meas. Sci. Technol. 20, 084017 (2009).
- B. Ren, L. Chen, R. Chen, R. Ji, and Y. Wang, “Noise Reduction of Atomic Force Microscopy Measurement Data for Fitting Verification of Chemical Mechanical Planarization Model,” Electronics 12, 2422 (2023).
- M. Checa, A. S. Fuhr, C. Sun, R. Vasudevan, M. Ziatdinov, I. Ivanov, S. J. Yun, K. Xiao, A. Sehirlioglu, Y. Kim, P. Sharma, K. P. Kelley, N. Domingo, S. Jesse, and L. Collins, “High-speed mapping of surface charge dynamics using sparse scanning Kelvin probe force microscopy,” Nat. Commun. 14, 1–12 (2023).
- D. Ziegler, T. R. Meyer, R. Farnham, C. Brune, A. L. Bertozzi, and P. D. Ashby, “Improved accuracy and speed in scanning probe microscopy by image reconstruction from non-gridded position sensor data,” Nanotechnology 24, 335703 (2013).
- R. W. Cole, T. Jinadasa, and C. M. Brown, “Measuring and interpreting point spread functions to determine confocal microscope resolution and ensure quality control,” Nat. Protoc. 6, 1929–1941 (2011).
- F. Pertl, J. C. Sobarzo, L. Shafeek, T. Cramer, and S. Waitukaitis, “Quantifying nanoscale charge density features of contact-charged surfaces with an FEM/KPFM-hybrid approach,” Phys. Rev. Mater. 6, 125605 (2022).
- C. D. Claxton and R. C. Staunton, “Measurement of the point-spread function of a noisy imaging system,” J. Opt. Soc. Am. A, JOSAA 25, 159–170 (2008).
- X. Zhang, T. Kashti, D. Kella, T. Frank, D. Shaked, R. Ulichney, M. Fischer, and J. P. Allebach, “Measuring the modulation transfer function of image capture devices: what do the numbers really mean?” in Proceedings Volume 8293, Image Quality and System Performance IX, Vol. 8293 (SPIE, 2012) pp. 64–74.
- M. Brouillard, N. Bercu, U. Zschieschang, O. Simonetti, R. Mittapalli, H. Klauk, and L. Giraudet, “Experimental determination of the lateral resolution of surface electric potential measurements by Kelvin probe force microscopy using biased electrodes separated by a nanoscale gap and application to thin-film transistors,” Nanoscale Adv. 4, 2018–2028 (2022).
- U. Zerweck, C. Loppacher, T. Otto, S. Grafström, and L. M. Eng, “Accuracy and resolution limits of Kelvin probe force microscopy,” Phys. Rev. B 71, 125424 (2005).
- Th. Glatzel, M. Ch. Lux-Steiner, E. Strassburg, A. Boag, and Y. Rosenwaks, “Principles of Kelvin Probe Force Microscopy,” in Scanning Probe Microscopy (Springer, New York, NY, New York, NY, USA, 2007) pp. 113–131.
- M. Salerno and S. Dante, “Scanning Kelvin Probe Microscopy: Challenges and Perspectives towards Increased Application on Biomaterials and Biological Samples,” Materials 11 (2018), 10.3390/ma11060951.
- D. Hoffman and D. Leibowitz, “Effect of Substrate Potential on Al2O3 Films Prepared by Electron Beam Evaporation,” J. Vac. Sci. Technol. 9, 326–329 (1972).
- F. Volmer, I. Seidler, T. Bisswanger, J.-S. Tu, L. R. Schreiber, C. Stampfer, and B. Beschoten, “How to solve problems in micro- and nanofabrication caused by the emission of electrons and charged metal atoms during e-beam evaporation,” J. Phys. D: Appl. Phys. 54, 225304 (2021).
- N. Turetta, F. Sedona, A. Liscio, M. Sambi, and P. Samorì, “Au(111) Surface Contamination in Ambient Conditions: Unravelling the Dynamics of the Work Function in Air,” Adv. Mater. Interfaces 8, 2100068 (2021).
- Y. Yu, D. Lee, and B. Jeong, “The dependence of the work function of Pt(111) on surface carbon investigated with near ambient pressure X-ray photoelectron spectroscopy,” Appl. Surf. Sci. 607, 155005 (2023).
- R. Bai, N. L. Tolman, Z. Peng, and H. Liu, “Influence of Atmospheric Contaminants on the Work Function of Graphite,” Langmuir 39, 12159–12165 (2023).
- H. Sugimura, Y. Ishida, K. Hayashi, O. Takai, and N. Nakagiri, “Potential shielding by the surface water layer in Kelvin probe force microscopy,” Appl. Phys. Lett. 80, 1459–1461 (2002).