PIEZOELECTRIC FORCE SENSOR FOR SCANNING FORCE MICROSCOPY

A dynamic scanning force microscope using a piezoelectric force sensor has been constructed. The complexity of the conventional dynamic SFM is due to the detector used for measuring the vibration amplitude of the cantilever. Our sensor enables direct detection of signals related to the lever amplitude by a piezoelectric layer formed on the lever. The sensor is a composite cantilever, which has a piezoelectric thin film layer sandwiched between electrode metals on a thermal SiO2 microbeam. The sensor is excited near the lever resonance by an external piezoelectric oscillator. Induced charge from the piezoelectric layer, which varies linearly with the lever amplitude, is detected for the feedback signal of an SFM. In this paper, we present a surface image of a 1 mum pitch grating, which was obtained by a dynamic SFM using the sensor in cyclic contact mode.