Ismail Muhammad, Mahata Chandreswar, Kang Myounggon, Kim Sungjun
Division of Electronics and Electrical Engineering, Dongguk University, Seoul, 04620, Republic of Korea.
Department of Electronics Engineering, Korea National University of Transportation, Chungju-si, 27469, Republic of Korea.
Nanoscale Res Lett. 2022 Jun 24;17(1):61. doi: 10.1186/s11671-022-03699-z.
For neuromorphic computing and high-density data storage memory, memristive devices have recently gained a lot of interest. So far, memristive devices have suffered from switching parameter instability, such as distortions in resistance values of low- and high-resistance states (LRSs and HRSs), dispersion in working voltage (set and reset voltages), and a small ratio of high and low resistance, among other issues. In this context, interface engineering is a critical technique for addressing the variation issues that obstruct the use of memristive devices. Herein, we engineered a high band gap, low Gibbs free energy AlO interlayer between the HfO switching layer and the tantalum oxy-nitride electrode (TaN) bottom electrode to operate as an oxygen reservoir, increasing the resistance ratio between HRS and LRS and enabling multilayer data storage. The Pt/HfO/AlO/TaN memristive device demonstrates analog bipolar resistive switching behavior with a potential ratio of HRS and LRS of > 10 and the ability to store multi-level data with consistent retention and uniformity. On set and reset voltages, statistical analysis is used; the mean values (µ) of set and reset voltages are determined to be - 2.7 V and + 1.9 V, respectively. There is a repeatable durability over DC 1000 cycles, 10 AC cycles, and a retention time of 10 s at room temperature. Quantum conductance was obtained by increasing the reset voltage with step of 0.005 V with delay time of 0.1 s. Memristive device has also displayed synaptic properties like as potentiation/depression and paired-pulse facilitation (PPF). Results show that engineering of interlayer is an effective approach to improve the uniformity, ratio of high and low resistance, and multiple conductance quantization states and paves the way for research into neuromorphic synapses.
对于神经形态计算和高密度数据存储存储器而言，忆阻器件近来引起了广泛关注。到目前为止，忆阻器件一直存在开关参数不稳定的问题，比如低电阻状态和高电阻状态（LRS和HRS）的电阻值失真、工作电压（设置和重置电压）分散以及高低电阻比率小等问题。在这种情况下，界面工程是解决阻碍忆阻器件应用的变化问题的一项关键技术。在此，我们在HfO开关层与氮氧化钽电极（TaN）底部电极之间设计了一个高带隙、低吉布斯自由能的AlO中间层，用作氧储存器，提高了HRS与LRS之间的电阻比，并实现了多层数据存储。Pt/HfO/AlO/TaN忆阻器件展示出模拟双极电阻开关行为，HRS与LRS的电位比大于10，并且具备存储多级数据的能力，数据保留性和均匀性良好。对于设置和重置电压，进行了统计分析；设置和重置电压的平均值（µ）分别确定为-2.7 V和+1.9 V。在室温下，经过1000次直流循环、10次交流循环以及10秒的保留时间后，具有可重复的耐久性。通过以0.005 V的步长增加重置电压并延迟0.1 s获得了量子电导。忆阻器件还表现出诸如增强/抑制和双脉冲易化（PPF）等突触特性。结果表明，中间层工程是提高均匀性、高低电阻比以及多导电量化状态的有效方法，为神经形态突触的研究铺平了道路。
