Piezo-generated charge mapping revealed through direct piezoelectric force microscopy. Issue 1 (December 2017) - Gomez, A.
Abstract While piezoelectric and ferroelectric materials play a key role in many everyday applications, there are still a number of open questions related to their physics. To enhance our understanding of piezoelectrics and ferroelectrics, nanoscale characterization is essential. Here, we develop an atomic force microscopy based mode that obtains a direct quantitative analysis of the piezoelectric coefficient d33 . We report nanoscale images of piezogenerated charge in a thick single crystal of periodically poled lithium niobate (PPLN), a bismuth ferrite (BiFO3 ) thin film, and lead zirconate titanate (PZT) by applying a force and recording the current produced by these materials. The quantification of d33 coefficients for PPLN (14 ± 3 pC per N) and BFO (43 ± 6 pC per N) is in agreement with the values reported in the literature. Even stronger evidence of the reliability of the method is provided by an equally accurate measurement of the significantly larger d33 of PZT. Piezoelectrics and ferroelectrics are important for everyday applications, but methods to characterize these materials at the nanoscale are lacking. Here the authors present direct piezoelectric force microscopy, an AFM mode that can measure charges generated by the direct piezoelectric effect with nanoscale resolution.