Fig. 1.

(a) Schematic depicting the method of using an AFM needle probe for intrinsically high Q factor AFM dynamic imaging in liquid. The setup keeps the AFM cantilever and the cantilever holder out of the liquid environment, and allows driving the cantilever directly with the piezostack in the cantilever holder to a high Q factor and high frequency resonance. (b) The calculated dependence of the Q factor versus the needle tip immersion length with the use of a needle of 600 nm, 300 nm and 150 nm in diameter.