High-Endurance Ferroelectric (La, Y) and (La, Gd) Co-Doped Hafnium Zirconate Grown by Atomic Layer Deposition

Abstract

Thin films based on stoichiometric hafnium zirconate doped and co-doped with La, Gd, and/or Y have been grown by atomic layer deposition on TiN electrodes. The resulting TiN−ferroelectric−TiN capacitors have shown high endurance up to 1 × 10 11 switching cycles. The simultaneous use of two dopants (Y, La) or (Gd, La) in hafnium zirconate increases the amount of orthorhombic and tetragonal phases. Fatigue-free capacitors with remnant polarization ≥15 μC/cm 2 at 1 × 10 11 endurance cycles have been obtained for dopants having an atomic fraction of about 1.2−1.8% and showing great promise as active materials for emerging memory applications.

Feasible Strategy for Large-Scale Production of 224Ra as a Promising α-Emitting Therapy Radionuclide

“…It was observed that the distribution coefficient of Th 4+ on the Dowex 1 × 8 resin increased with the concentration of HNO 3 , reaching a maximum value of 237.29 mL·g –1 in 9 M HNO 3 . In 9 M HNO 3 , Th 4+ predominantly exists as Th­(NO 3 ) 6 . − Therefore, it can undergo a Cl – exchange with Dowex 1 × 8 anion exchange resin, resulting in its strong adsorption onto the resin. On the other hand, Ba, Y, and La remained in their cationic forms under these conditions and can be directly eluted from the Dowex 1 × 8 resin.…”

Recent progress on defect-engineering in ferroelectric HfO2: The next step forward via multiscale structural optimization

“…Patrick et al 99 reported Al + Si co-doped HfO 2 with remnant polarization of ∼20 μC cm −2 and enhanced endurance up to 10 8 cycles. Mihaela et al 98 investigated La + Y/Gd co-doped HZO, and as shown in Fig. 10, the (Y, La) or (Gd, La) co-doped HZO thin films were found to increase the amount of o- and t- phases (Fig.…”

“…Mihaela et al 98 investigated La + Y/Gd co-doped HZO, and as shown in Fig. 10, the (Y, La) or (Gd, La) co-doped HZO thin films were found to increase the amount of o-and t-phases (Fig.…”

Hafnia-Based Ferroelectric Memory: Device Physics Strongly Correlated with Materials Chemistry

“…(a) Endurance and remanent polarization ( P r ) from various previous studies, as reproduced from a previous publication by Park et al References [a] to [o] are referred from refs and − in the same order. Panel a was reproduced with permission from ref .…”