Piezoelectric coefficient measurement of piezoelectric thin films: an overview

An overview on the state-of-art piezoelectric measurements of thin films is given. The principles and advantages/disadvantages of the conventional techniques are discussed for piezoelectric applications. Concerning a direct measurement of piezoelectric coefficient and taking into account of 1.0–100.0 μm in film thickness, a displacement of 0.1 nm cannot be reliably detected by utilizing the reverse piezoelectric effect, unless the probe’s resolution reaches up to 10−3 nm. The sensitivity of charge-integrator cannot be worse than ∼0.1 nC, typically. Such a high resolution in terms of displacement and charge may not be always reachable if the measurement is not carefully calibrated and manipulated. New demands on the techniques have been placed and a more careful selection of the techniques to be used is required.