BEOL Compatible Ultra-Low Operating Voltage (0.5 V) and Preconfigured Switching Polarization States in Effective 3 nm Ferroelectric HZO Capacitors

Abstract

We report the record-high remanent polarization value (2P<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">r</inf> ~55 μC/cm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>) at an ultra-low operating voltage (0.5 V) with effective 3 nm hafnium zirconium oxide (HZO) capacitors. This exceptional ferroelectric property is achieved at a back-end-of-line (BEOL) compatible temperature below 400°C. Moreover, our devices demonstrate configurable ferroelectric saturation characteristics, ensuring reliable and reproducible switching polarization states <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(\mathrm{P}_{\text{sw}})$</tex>. These results potentially allow the design of novel ferroelectric device circuitry. This study highlights the feasibility of extremely low-power ferroelectric applications beyond 0.5 V operation in BEOL.