Lancaster Suzanne, Remillieux Maximilien, Engl Moritz, Havel Viktor, Silva Cláudia, Wang Xuetao, Mikolajick Thomas, Slesazeck Stefan
NaMLab gGmbH, Nöthnitzer Str. 64a, Dresden 01187, Germany.
École Supérieure de Chimie Physique Électronique de Lyon, 3 Rue Victor Grignard, Villeurbanne 69100, France.
ACS Appl Mater Interfaces. 2024 Sep 25;16(38):51109-51117. doi: 10.1021/acsami.4c10338. Epub 2024 Sep 12.
Ferroelectric tunnel junctions (FTJs) are a class of memristor which promise low-power, scalable, field-driven analog operation. In order to harness their full potential, operation with identical pulses is targeted. In this paper, several weight update schemes for FTJs are investigated, using either nonidentical or identical pulses, and with time delays between the pulses ranging from 1 μs to 10 s. Experimentally, a method for achieving nonlinear weight update with identical pulses at long programming delays is demonstrated by limiting the switching current via a series resistor. Simulations show that this concept can be expanded to achieve weight update in a 1T1C cell by limiting the switching current through a transistor operating in subthreshold or saturation mode. This leads to a maximum linearity in the weight update of 86% for a dynamic range (maximum switched polarization) of 30 μC/cm. It is further demonstrated via simulation that engineering the device to achieve a narrower switching peak increases the linearity in scaled devices to >93% for the same range.
铁电隧道结（FTJ）是一类忆阻器，有望实现低功耗、可扩展的场驱动模拟操作。为了充分发挥其潜力，目标是使用相同的脉冲进行操作。本文研究了几种用于FTJ的权重更新方案，使用不相同或相同的脉冲，脉冲之间的时间延迟范围为1微秒至10秒。在实验上，通过串联电阻限制开关电流，展示了一种在长编程延迟下用相同脉冲实现非线性权重更新的方法。模拟表明，通过限制在亚阈值或饱和模式下工作的晶体管的开关电流，这一概念可以扩展到在1T1C单元中实现权重更新。对于30微库仑/平方厘米的动态范围（最大开关极化），这导致权重更新的最大线性度为86%。通过模拟进一步证明，设计器件以实现更窄的开关峰值，对于相同范围，可将缩放器件中的线性度提高到>93%。
