Ferroelectrics at the nanoscale: materials and devices–a critical review

Following the initial report on ferroelectricity in hafnia (HfO₂) more than a decade ago, the researchers’ interest in this intriguing material system has constantly increased due to the promise it holds for future applications. Currently, there is an unbalanced situation, where an overwhelming majority of studies focus on either nanoscale characterization or on tuning the growth conditions in view of improving the properties of HfO₂, but only few applications of this material system are being investigated. The goal of this review is to provide an overview of all emerging nanoscale ferroelectrics, to review their integration in most promising devices and to provide a critical analysis addressing the detrimental physical effects of nanoscale ferroelectrics on the performance of devices while outlining the perspectives to alleviate these adverse effects.