Area Scalable Hafnium-Zirconium-Oxide Ferroelectric Capacitor Using Low-Temperature Back-End-of-Line Compatible 40°C Annealing
Journal
2022 International Symposium on VLSI Technology, Systems and Applications, VLSI-TSA 2022
Date Issued
2022
Author(s)
Abstract
Improving the area scalability and reducing the process temperature of Hf0.5Zr0.5O2 (HZO) ferroelectric (FE) capacitors are two of the most critical challenges in future back-end-of-line (BEOL) compatible FE memories. This paper presents the first study demonstrating the existence of a tradeoff between the area scalability and the annealing temperature, suggesting that these two should be optimized simultaneously rather than separately. Optimizing the HZO thickness and Hf:Zr ratio are identified to improve the tradeoff. High remanent polarization density of 24 µC/cm2 and excellent endurance of 9×109 cycles are achieved in a scaled FE area as small as 0.6×0.6 µm2 by using the BEOL-compatible 400°C annealing. © 2022 IEEE.
Other Subjects
Annealing; Ferroelectricity; Hafnium oxides; Temperature; Zirconium compounds; Annealing temperatures; Back end of lines; Critical challenges; Ferroelectric capacitors; Ferroelectric memory; Lows-temperatures; Polarization density; Process temperature; Zirconia oxide; Scalability
Type
conference paper