Ferroelectric Field-Effect Transistors—Logic Compatibility and Microstructure

Over the last decade, the discovery of ferroelectricity in fluorite-structured binary oxides, namely HfO₂ and its alloyed variant, led to resurgent interests into ferroelectric devices for embedded memory applications [1,2]. In this talk, we will highlight recent advancements in ferroelectric field-effect transistors (FEFETs). First, we will present our work on reducing write voltage in FEFETs down to logic compatible levels for embedded memory applications by engineering the interfacial oxide layer and gate metal electrodes. Next, we will highlight our efforts on understanding and controlling the microstructure of ferroelectric layer in FEFET gate stacks to address the variability challenge, using multi-scale transmission electron microscopy including in-situ, electrical biasing approaches [3]. The talk will end with an outlook for FEFETs for different domains, such as embedded, storage class and storage applications.<br/><br/>The research is supported by the National Science Foundation, the Defense Advanced Research Program Agency (DARPA), the Applications and Systems-Driven Center for Energy-Efficient Integrated Nano Technologies (ASCENT), one of six centers in the Joint University Microelectronics Program (JUMP), a SRC program sponsored by the DARPA, and an Intel Rising Star award.<br/><br/>[1] Mikolajick, T., Schroeder, U. & Slesazeck, S. The past, the present, and the future of ferroelectric memories. IEEE Trans. Electron Devices 67,<br/>1434–1443 (2020).<br/>[2] Asif Islam Khan, Ali Keshavarzi, and Suman Datta. “The future of ferroelectric field-effect transistor technology." <i>Nature Electronics</i> 3.10 (2020): 588-597.<br/>[3] Sarah Lombardo <i>et al</i>. "Atomic-scale imaging of polarization switching in an (anti-) ferroelectric memory material: Zirconia (ZrO2)."2020 IEEE Symposium on VLSI Technology. IEEE, 2020.