Guido Roberto, Mikolajick Thomas, Schroeder Uwe, Lomenzo Patrick D
Namlab gGmbH, Nöthnitzer Strasse 64a, 01187 Dresden, Germany.
Chair of Nanoelectronics, TU Dresden, 01187 Dresden, Germany.
Nano Lett. 2023 Aug 9;23(15):7213-7220. doi: 10.1021/acs.nanolett.3c02351. Epub 2023 Jul 31.
Aluminum scandium nitride (AlScN), with its large remanent polarization, is an attractive material for high-density ferroelectric random-access memories. However, the cycling endurance of AlScN ferroelectric capacitors is far below what can be achieved in other ferroelectric materials. Understanding the nature and dynamics of the breakdown mechanism is of the utmost importance for improving memory reliability. The breakdown phenomenon in ferroelectric AlScN is proposed to be an impulse thermal filamentary-driven process along preferential defective pathways. For the first time, stable and robust bipolar filamentary resistive switching in ferroelectric AlScN is reported. A hot atom damage defect generation model illustrates how filament formation and ferroelectric switching are connected. The model reveals the tendency of the ferroelectric wurtzite-type AlScN system to reach internal symmetry with bipolar electric field cycling. Defects generated from bipolar electric field cycling influence both the energy barrier between the polarization states and that required for the filament formation.
氮化铝钪（AlScN）具有较大的剩余极化，是用于高密度铁电随机存取存储器的一种有吸引力的材料。然而，AlScN铁电电容器的循环耐久性远低于其他铁电材料所能达到的水平。了解击穿机制的本质和动力学对于提高存储器可靠性至关重要。铁电AlScN中的击穿现象被认为是沿着优先缺陷路径的脉冲热丝状驱动过程。首次报道了铁电AlScN中稳定且稳健的双极丝状电阻开关。一个热原子损伤缺陷产生模型说明了丝状形成与铁电开关是如何联系的。该模型揭示了铁电纤锌矿型AlScN系统在双极电场循环下达到内部对称性的趋势。双极电场循环产生的缺陷既影响极化状态之间的能垒，也影响丝状形成所需的能垒。
