This paper presents a study on the dynamic response of an atomic force microscope (AFM) cantilever with a solid state heating element in liquid and its application for measuring the temperature-dependent viscosity of liquids. A finite difference model (FDM) predicts the frequency response of a heated cantilever immersed in liquid and calibrates the liquid viscosity from the measured cantilever resonant frequency (f) at different cantilever heater temperatures. The technique measures a wide range of liquid viscosities (0.0005-0.005 kgms) at temperatures ranging from 20 to 55 °C with high sensitivity (7.1 × 10 kgms/Hz for 50 wt% ethylene glycol/water). The measurement requires heating a liquid volume of about 10 nl, which is more than 1000X smaller than other microcantilever-based viscosity measurements.
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