Parts | Days | Selection | Search | Updates | Downloads | Help

MI: Fachverband Mikrosonden

MI 8: Poster – Microanalysis and microscopy

MI 8.11: Poster

Wednesday, March 28, 2012, 15:00–17:30, Poster E

Precise determination of force microscopy cantilever stiffness from dimensions and eigenfrequencies — •Jannis Lübbe¹, Lutz Doering², and Michael Reichling¹ — ¹Fachbereich Physik, Universität Osnabrück, Barbarastraße 7, 49076 Osnabrück, Germany — ²PTB, Nano- and Micrometrology, Bundesallee 100, 38116 Braunschweig, Germany

We demonstrate the non-destructive measurement of the stiffness of silicon cantilevers with tips as used for non-contact atomic force microscopy (NC-AFM) from the knowledge of cantilever dimensions and eigenfrequencies. The calculation of the stiffness is based on dimensions derived from scanning electron microscopy, optical microscopy and laser interferometry measurements. This yields stiffness values with an uncertainty of ±25% as the result critically depends on the thickness of the cantilever that is experimentally difficult to be determined. The uncertainty is reduced to ±7% when the measured fundamental eigenfrequency is included in the calculation and a tip mass correction is applied. The tip mass correction can be determined from the eigenfrequencies of the fundamental and first harmonic modes. Results are verified by tip destructive measurements of the stiffness with a precision instrument recording a force-bending curve yielding an uncertainty better than ±5%.