In-Grain Ferroelectric Switching in Sub-5 nm Thin Al Sc N Films at 1 V.

Analog switching in ferroelectric devices promises neuromorphic computing with the highest energy efficiency if limited device scalability can be overcome. To contribute to a solution, one reports on the ferroelectric switching characteristics of sub-5 nm thin Al Sc N films grown on Pt/Ti/SiO /Si and epitaxial Pt/GaN/sapphire templates by sputter-deposition. In this context, the study focuses on the following major achievements compared to previously available wurtzite-type ferroelectrics: 1) Record low switching voltages down to 1 V are achieved, which is in a range that can be supplied by standard on-chip voltage sources.

Thermal Stability of the Ferroelectric Properties in 100 nm-Thick AlScN.

The discovery of ferroelectricity in aluminum scandium nitride (AlScN) opens technological perspectives for harsh environments and space-related memory applications, considering the high-temperature stability of piezoelectricity in aluminum nitride. The ferroelectric and material properties of 100 nm-thick AlScN are studied up to 873 K, combining both electrical and in situ X-ray diffraction measurements as well as transmission electron microscopy and energy-dispersive X-ray spectroscopy. The present work demonstrates that AlScN can achieve high switching polarization and tunable coercive fields in a 375 K temperature range from room temperature up to 673 K.