Self-oscillating tapping mode atomic force microscopy

A piezoelectric microcantilever probe is demonstrated as a self-oscillator used for tapping mode atomic force microscopy. The integrated piezoelectric film on the cantilever serves as the frequency-determining component of an oscillator circuit; oscillation near the cantilever's resonant frequency is maintained by applying positive feedback to the film via this circuit. This new mode, which is a step towards more compact and parallel tapping mode AFM imaging, is demonstrated by imaging an evaporated gold film on a silicon substrate. A self-oscillating frequency spectrum and a force-distance curve are also presented. (C) 2003 American Institute of Physics.