Characterizing Atomic Force Microscope Cantilevers Using a Precision Balance

摘要

Motivated by emerging needs of accurate force measurements in nanotechnology and biotechnology areas, more than adozen calibration methods have been suggested. In this paper, we present a new calibration system, 'Nano Force Calibrator (NFC)', in which a precision balance is involved, and calibration results of two types of AFM cantilevers using the NFC system. The NFC system shows good reproducibility of calibration results with less than 0.7 percent. The calibration results tell us that the spring constants of AFM cantilevers differ from the nominal value specified by manufacturers (up to 240 percent). Also, they are not quite equal to each other even if they are fabricated from same wafer. On the contrary, in case of the reference levers used for calibrating other AFM cantilevers, the deviations of spring constants from nominal value are relatively low (up to 7.5 percent).