The Rise of Ferroelectricity at Nanoscale: Nanoelectronics is rediscovering the ferroelectricity

We present a comprehensive review of the emerging nanoscale ferroelectric materials used in novel nanoelectronics devices. First, we outline specific physical and electronic properties of ferroelectric materials, then we focus on two main classes of ferroelectrics based on hafnium oxide (HfO₂) and 2D materials. The former exhibits unique characteristics, making it the target of subsequent discussions. Their remanent polarization, coercive field, permittivity, nanometric scale thickness (up to 10 nm), and CMOS compatibility distinguish HfO₂ compounds from any other existing ferroelectrics. The ever increasing need to integrate nanotechnology with electronics has given rise to the realization of newer conceptual devices and components based on ferroelectric HfO₂, such as phase shifters, phased antenna arrays (PAAs), filters, field-effect transistors (FETs,) ferroelectric tunneling junctions (FTJs), memristors/memtransistors (neuromorphic nanoelectronics), and negative capacitance ferroelectric transistors. For each of these applications, we present state-of-the-art solutions that were designed, fabricated, and tested. At the same time, the main drawbacks (especially those related to materials and technological issues) are discussed. This article provides an in-depth overview of present and future challenges in the domain of ferroelectric-based nanoelectronics, with the hope that it will trigger the curiosity of researchers interested in the further advancement of this emerging field of science.