HfO₂-Based Ferroelectrics Applications in Nanoelectronics

This article is dedicated to HfO₂-based ferroelectrics applications in nanoelectronics, especially to topics not well developed up to now, such as microwaves, energy harvesting, and neuromorphic devices working as artificial neurons and synapses. Other well-covered topics in the literature, such as memories or negative-capacitance ferroelectric field-effect transistors, will be only briefly mentioned. The main impact of HfO₂-based ferroelectrics is the possibility of using them for fabricating at the wafer-level complementary metal oxide semiconductor (CMOS) compatible high-frequency devices, such as phase-shifters, antenna arrays, or filters with a high degree of tunability and miniaturization, as well as energy harvesting devices and neuromorphic key components. In addition, the recent transfer of 2D materials on HfO₂ ferroelectrics has demonstrated new physical effects, such as opening a 0.2 eV bandgap in graphene monolayers, and allows the manufacture of very high-mobility field-effect transistors (FETs) based on graphene/HfZrO.