Imaging, handling and manipulation of material with high resolution are important techniques for various applications of research. Atomic force microscopes (AFM) are one of the most important tools for imaging applications with spatial resolution beyond the diffraction limit of light. The project aims is to build a complete AFM-system, including advanced imaging modes, in cooperation with Anton Paar GmbH.

Project focus

• High-speed and long stroke Z-actuator
• Design and implementation of high-speed and low-noise laser-deflection readout system
• Development of a scanning-lever AFM-system
• Development of advanced measurement modes

Description

Imaging, handling and manipulation of material with high resolution are important techniques for various applications of research. Atomic force microscopes (AFM) are one of the most important tools for imaging applications with spatial resolution beyond the diffraction limit of light. The project aims is to build a complete AFM-system, including advanced imaging modes, in cooperation with Anton Paar GmbH. The work packages belonging to ACIN includes the development of the AFM-head components, high-speed, vertical Z-actuator, high-speed and low-noise laser-deflection readout system, scanning-lever AFM-system and advanced measurement modes. A follow-up project was focused on the development of functional imaging-modes. Various research fields such as biology, physics or materials science are using such functional imaging-modes like Kelvin-probe force microscopy (KPFM). With KPFM it is possible to map the sample surface potential in a quantitative way with nanometer resolution. At MPEI, a novel feedback based Scanning Probe Microscopy method which enables quantitative surface potential measurements without the need of the DC bias of Kelvin Probe Force Microscopy was developed. This method opens the way to image the surface potential of various samples such as semiconductors or biological cells without the need for applying a disturbing or interfering DC-bias and enables new applications of feedback based KPFM technologies.

Fig. 1 Comparison of classical KPFM and AC-KPFMy of a positive charge pattern on PMMA. Topography (A) and surface potential V recorded with classical KPFM (B). (C) amplitude b and (D) surface potential V = −b2 acquired with AC-KPFMy of the same pattern as in (B). The images (C) and (D) were recorded immediately after (A) and (B) without disengaging the tip.

Applications

• Nanometrology Systems
• AFM, SPM, KPFM, EFM, MFM, QNM etc.

Related Publications

• D. Kohl, P. Mesquida, and G. Schitter, Multi-frequency Kelvin Probe Force Microscopy Method for Charge Mapping Without DC-Bias, in Nano and Photonics & FemtoMat 2017, 2017.
• D. Kohl, P. Mesquida, and G. Schitter, Quantitative DC-free Kelvin Probe Force Microscopy, in Final Program 42nd International Conference on Micro and Nano Engineering, 2016.
• R. Saathof, T. Riel, M. Bibl, D. Kohl, H. W. Yoo, and G. Schitter, Non-parametric robustness analysis for feedback motion control for a high precision stage with large mass uncertainty, in Proceedings of the 2016 American Control Conference, 2016, p. 2611–2616.
• D. Kohl, T. Riel, R. Saathof, J. Steininger, and G. Schitter, Auto-Tuning PI Controller for Surface Tracking in Atomic Force Microscopy – A Practical Approach, in Proceedings of the 2016 American Control Conference, 2016.
• J. Steininger, M. Bibl, H. W. Yoo, and G. Schitter, High bandwidth deflection readout for atomic force microscopes, Review of Scientific Instruments, vol. 86, 2015.
• J. Steininger, R. Paris, and G. Schitter, Increasing sensitivity while reducing crosstalk of the force sensor in atomic force microscopes, in Proceedings of the 14th International Conference of the European Society for Precision Engineering and Nanotechnology, 2014, p. 321–324.
• J. Steininger, R. Paris, and G. Schitter, Improving the Deflection Readout Mechanism of an Atomic Force Microscope, in MESS14 Microelectronic Systems Symposium, Band 76 der OVE-Schriftenreihe, 76, 2014, p. 22.
• J. Steininger and G. Schitter, Influence of the Photodetector Geometry on the Deflection Measurement in Atomic Force Microscopes, in Proceedings of the ASPE 2014 Annual Meeting, 2014, p. 674–679.
• J. Steininger, S. Kuiper, S. Ito, and G. Schitter, Schnelle Rasterkraftmikroskopie durch moderne Regelungstechnik und mechatronische Systemintegration, E&I Elektrotechnik und Informationstechnik, vol. 129, iss. 1, p. 28–33, 2012.

Project partners

• Anton Paar GmbH

Funding

• Austrian Research Promotion Agency (FFG)
• Anton Paar GmbH