A high-eigenfrequency differential stiffness probe for high-speed scanning probe microscopy.

Autor: Dey, S., Agrawal, S., Kartik, V.
Předmět:
Zdroj: Proceedings of the Royal Society A: Mathematical, Physical & Engineering Sciences; 10/25/2023, Vol. 479 Issue 2278, p1-18, 18p
Abstrakt: Microcantilever probes used for high-speed scanning probe microscopy are typically required to satisfy two mutually contradicting objectives: high eigenfrequency (ωn) and low flexural rigidity (kb). The conventional design approach shortens the microcantilever's length to increase the eigenfrequencies (as ωn∝1/L2); however, this also increases the probe's rigidity (as kb∝1/L3). This paper demonstrates—through experiments and physical modelling—the design of a novel high-eigenfrequency probe by redistributing the microcantilever's mass along its length. A 100% increase in the probe's eigenfrequency is achieved with this modified design, even while reducing its stiffness by 50%. Through experiments, this reduced stiffness has been found to enhance the probe's force sensitivity. Also, the probe's design facilitates redistributing the fluid pressure between its underside surface and the sample, thereby improving the quality factor by more than 100%. Significant reduction in 'overshoot' and 'parachute' is observed in contact mode scanning at the video rate. The improvements in the image resolution are proven for a variety of sample surfaces at very high scan rates up to 40 Hz (corresponding to a linear speed of 3.20 mm s−1) upon scanning over an area of 40×40 μm and are successfully demonstrated to map topographies with negligible image artefacts. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index