Multimodal Chemical and Functional Imaging of Nanoscale Transformations in Ferroelectric Thin Films

Continuing miniaturization of portable electronic and mechanical devices requires development of the novel nanoscale elements. This can be realized using ferroelectric materials, which exhibit a unique set of functional properties, including pyroelectricity, piezoelectricity, non-linear optical activity and others. These properties enable a wide range of practical applications from sensors and actuators to data storage and processing devices [1-3]. However, functionality of ferroelectric materials is defined by the number of physical and chemical phenomena on the nanoscale, which requires using of the nanoscale imaging techniques allowing functional and chemical investigations. Atomic Force Microscopy (AFM) is one of such techniques. Various AFM electric modes are widely used for characterization of the ferroelectric physical properties on the nanoscale [4]. But at the same time, chemical contribution in the ferroelectric phenomena in the most cases are completely ignored due to the lack of tools for nanoscale chemical investigations. These studies can be carried out by combination of AFM with concomitant microscopic or spectroscopic technique, providing chemical or crystallographic information about studied sample [5]. One of such cases if offered by combination with Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS), which allows local investigation of the chemical composition on the sample surface and in the sample bulk [6].