Piezoelectric PZT Cantilever Array Integrated with Piezoresistor for High Speed Operation and Calibration of Atomic Force Microscopy

Abstract

Two kinds of PZT cantilevers integrated with a piezoresistor have been newly designed, fabricated, and characterized for high speed AFM. In first cantilever, a piezoresistor is used to sense atomic force acting on tip, while in second cantilever, a piezoresistor is integrated to calibrate hysteresis and creep phenomena of the PZT cantilever. The fabricated PZT cantilevers provide high tip displacement of 0.55μm/V and high resonant frequency of 73 kHz. A new cantilever structure has been designed to prevent electrical coupling between sensor and PZT actuator and the proposed cantilever shows 5 times lower coupling voltage than that of the previous cantilever. The fabricated PZT cantilever shows a crisp scanned image at 1mm/sec, while the conventional piezo-tube scanner shows blurred image even at 180μm/sec. The non-linear properties of the PZT actuator are also well calibrated using the piezoresistive sensor for calibration.