Motivated by emerging needs for accurate force measurements in the nanotechnology and biophysics areas, we present an atomic force microscope (AFM) cantilever calibration system, the ‘nano force calibrator’ (NFC), consisting of a microbalance and a precision translation stage. Calibration using the NFC has proved to be a reliable and accurate method through a series of experiments with a commercial piezoresistive AFM cantilever. In these experiments, linearity, repeatability and reproducibility of measurements were investigated along with the effects of calibration conditions, such as orientation of the cantilever and temperature. Uncertainty analysis shows that the stiffness and force sensitivity are determined to be 3.385 N m−1 and 0.6490 µN Ω−1, which are traceable to the Système International d'Unités (SI units). The relative standard uncertainties of both the stiffness and sensitivity are approximately 0.4% or conservatively 0.5%.

This paper describes the dynamic characteristics of a binocular six-component force-moment sensor with force components Fx, Fy and Fz, each having 200 N capacity, and moment components Mx, My and Mz, each having 20 N m capacity. We have evaluated the dynamic characteristics of the force-moment sensor by using a shaker system and a multichannel dynamic analyser system. It reveals that the sensitivity decreases as the frequency increases and that the sensor shows almost 90° symmetry due to its geometry.

We have demonstrated the feasibility of using the nano force calibrator (NFC), consisting of a microbalance and a nano-stage, as a calibration device, which can accurately determine normal spring constants (k) of various atomic force microscope (AFM) cantilevers with traceability to the Système International d'Unités (SI units). From very compliant (k < 0.1 N m−1) to stiff (k > 10 N m−1) cantilevers, three types of commercial levers with different shapes (beam and V) and operating modes (contact and tapping) were chosen to test NFC calibration performances. We have found that all types of levers could be well characterized by the NFC even when a small force (approximately 500 nN) was used to calibrate a soft cantilever (k < 0.1 N m−1). We declared the relative standard uncertainty of the spring constant calibration of our method to be better than 1%, based on calibration results and uncertainty analysis. Because of its small calibration uncertainty, the NFC is recommendable for accurate calibration of AFM cantilevers and as a reference method for assessing other popularly used calibration methods.

This paper describes the dynamic characteristics of a three-component force-moment sensor with the transverse forces Fx and Fy each having 200 N capacity and a twisting moment Mz of 10 N m capacity. We have evaluated the dynamic characteristics of the force-moment sensor by using a shaker system and a multi-channel dynamic analyser system. It reveals that the sensitivity decreases as the frequency increases and that the sensor has a 90° symmetry due to its geometry.

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