Al_0.68Sc_0.32N/SiC-Based Metal-Ferroelectric-Semiconductor Capacitors Operating up to 1000 °C

Ferroelectric (Fe) materials-based devices show great promise for nonvolatile memory applications, yet few demonstrate reliable operation at elevated temperatures. In this work, we demonstrate Ni/Al_0.68Sc_0.32N/4H-SiC metal-ferroelectric-semiconductor capacitors for high-temperature nonvolatile memory applications. Our 30 nm thick ferroelectric Al_0.68Sc_0.32N film grown on SiC exhibits stable and robust ferroelectric switching up to 1000 °C. The coercive field decreases linearly from -6.4/+11.9 MV cm^-1 at room temperature to -3.1/+7.8 MV cm^-1 at 800 °C, further reducing to -2.5 MV cm^-1 at 1000 °C. At 600 °C, the devices achieve remarkable reliability with ∼2000 endurance cycles and over at least 100 h of retention with negligible polarization loss. At 800 °C, the devices retain data for at least 10,000 s and exceed 400 write cycles. Our results further highlight the potential for ferroelectric AlScN thin films particularly when paired with SiC semiconductor substrates for high-temperature nonvolatile memory.