Yang Seyeong, Kim Taegyun, Kim Sunghun, Chung Daewon, Kim Tae-Hyeon, Lee Jung Kyu, Kim Sungjoon, Ismail Muhammad, Mahata Chandreswar, Kim Sungjun, Cho Seongjae
Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, South Korea.
School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
Nanoscale. 2023 Aug 17;15(32):13239-13251. doi: 10.1039/d3nr01930f.
Although vertical configurations for high-density storage require challenging process steps, such as etching high aspect ratios and atomic layer deposition (ALD), they are more affordable with a relatively simple lithography process and have been employed in many studies. Herein, the potential of memristors with CMOS-compatible 3D vertical stacked structures of Pt/Ti/HfO/TiN-NCs/HfO/TiN is examined for use in neuromorphic systems. The electrical characteristics (including - properties, retention, and endurance) were investigated for both planar single cells and vertical resistive random-access memory (VRRAM) cells at each layer, demonstrating their outstanding non-volatile memory capabilities. In addition, various synaptic functions (including potentiation and depression) under different pulse schemes, excitatory postsynaptic current (EPSC), and spike-timing-dependent plasticity (STDP) were investigated. In pattern recognition simulations, an improved recognition rate was achieved by the linearly changing conductance, which was enhanced by the incremental pulse scheme. The achieved results demonstrated the feasibility of employing VRRAM with TiN nanocrystals in neuromorphic systems that resemble the human brain.
尽管用于高密度存储的垂直结构需要具有挑战性的工艺步骤，如蚀刻高深宽比和原子层沉积（ALD），但它们通过相对简单的光刻工艺成本更低，并且已在许多研究中得到应用。在此，研究了具有Pt/Ti/HfO/TiN-NCs/HfO/TiN的CMOS兼容3D垂直堆叠结构的忆阻器在神经形态系统中的应用潜力。研究了平面单电池和各层垂直电阻式随机存取存储器（VRRAM）电池的电学特性（包括 - 特性、保持性和耐久性），证明了它们出色的非易失性存储能力。此外，还研究了不同脉冲方案下的各种突触功能（包括增强和抑制）、兴奋性突触后电流（EPSC）和尖峰时间依赖性可塑性（STDP）。在模式识别模拟中，通过线性变化的电导实现了提高的识别率，该电导通过增量脉冲方案得到增强。所取得的结果证明了在类似于人类大脑的神经形态系统中采用带有TiN纳米晶体的VRRAM的可行性。
