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This content will become publicly available on August 25, 2023

Title: Large remnant polarization and great reliability characteristics in W/HZO/W ferroelectric capacitors
In this work, the effect of rapid thermal annealing (RTA) temperature on the ferroelectric polarization in zirconium-doped hafnium oxide (HZO) was studied. To maximize remnant polarization (2P r ), in-plane tensile stress was induced by tungsten electrodes under optimal RTA temperatures. We observed an increase in 2P r with RTA temperature, likely due to an increased proportion of the polar ferroelectric phase in HZO. The HZO capacitors annealed at 400°C did not exhibit any ferroelectric behavior, whereas the HZO capacitors annealed at 800°C became highly leaky and shorted for voltages above 1 V. On the other hand, annealing at 700 °C produced HZO capacitors with a record-high 2P r of ∼ 64 μ C cm −2  at a relatively high frequency of 111 kHz. These ferroelectric capacitors have also demonstrated impressive endurance and retention characteristics, which will greatly benefit neuromorphic computing applications.
Authors:
; ; ; ; ; ; ; ; ; ; ; ; ;
Award ID(s):
2023752
Publication Date:
NSF-PAR ID:
10354311
Journal Name:
Frontiers in Materials
Volume:
9
ISSN:
2296-8016
Sponsoring Org:
National Science Foundation
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