A transversal approach to predict surface charge compensation in piezoelectric force microscopy

Piezoelectric force microscopy (PFM) has demonstrated to be a powerful tool characterize ferroelectric materials. However, extrinsic effects, most notably, those resulting from surface charges, often mask or mirror genuine piezoelectric response, challenging PFM data understanding. The contribution of charges signal is commonly compensated by using appropriate external bias voltage, which ad-hoc selected and sample dependent. Here, we determine the compensating voltage in thin films different materials compare with corresponding I-V characteristics recorded suitable electrodes. It turns out that sign magnitude required compensate are related asymmetry characteristics. We propose this relation results fact semiconducting properties material both dependence, charged adsorbates. show how make use correlation predict compensation non-ferroelectric spurious piezoelectric-like contributions largely cancelled. provide guidelines mitigate common imaging.