Novel Small Cantilever

• Applicants: Professor Dr.-Ing. Thomas Fröhlich; Professor Dr.-Ing. Ivo W. Rangelow
• Subject Area: Measurement Systems ; Microsystems
• Term: from 2017 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 327297123

Atomic Force Microscopy (AFM) allows for micrographs of a millionfold magnification and hence visualization of single molecules and even atoms. During the last 25 years it has become a standard analytics tool in a number of research fields. For future applications in biotechnology or life sciences, there are two requirements of particular importance: For the display of biological processes in and at living cells, a frame rate comparable with the speed of the proceeding processes is required. Therefore cantilevers with a high resonance frequency are needed. At the same time, these cantilevers have to have a low spring constant, to avoid a mechanical damaging of cells or biofilms.Furthermore, such cantilevers are used to measure mechanical properties such as the stiffness of biological cells (e.g. force spectroscopy of cancer cells). For truly quantitative and comparable force measurements, a traceable calibration of the spring constants with low uncertainties is urgently required. At present, no cantilevers with both high resonance frequencies and low spring constants are available, which are in addition calibrated traceable with low forces. The required high resolving calibration systems are not available at present.The proposed project addresses exactly these missing items. Both novel small cantilevers with both high resonance frequencies and low spring constants, as well as a new high resolving measurement method for the investigation of the links and the calibration of the spring constants shall be developed and researched.The fundamental discrepancy between a high resonance frequency and a low spring constant at the same time, shall be dissolved by the development of novel small cantilevers with small dimensions and hence a low mass.The required high force resolution of the measurement and calibration system for the spring constants shall be achieved by a simplification of its mechanics and consequently an increase of the force sensitivity and decrease of sensitivity to disturbances.

• DFG Programme: Research Grants
• Co-Investigators: Tzvetan Ivanov, Ph.D.; Dr.-Ing. Michael Kühnel; Dr.-Ing. Ilko Rahneberg; Dr. Jens-Peter Zöllner