All-Electrical Control of Compact SOT-MRAM: Toward Highly Efficient and Reliable Non-Volatile In-Memory Computing

Huai Lin; Xi Luo; Long Liu; Di Wang; Xuefeng Zhao; Ziwei Wang; Xiaoyong Xue; Feng Zhang; Guozhong Xing

doi:10.3390/mi13020319

All-Electrical Control of Compact SOT-MRAM: Toward Highly Efficient and Reliable Non-Volatile In-Memory Computing

Micromachines (Basel). 2022 Feb 18;13(2):319. doi: 10.3390/mi13020319.

Authors

Huai Lin^{1

2}, Xi Luo³, Long Liu^{1

2}, Di Wang^{1

2}, Xuefeng Zhao^{1

4}, Ziwei Wang^{1

2}, Xiaoyong Xue⁵, Feng Zhang¹, Guozhong Xing^{1

2}

Affiliations

¹ Key Laboratory of Microelectronic Devices & Integrated Technology, Institute of Microelectronics, Chinese Academy of Sciences, Beijing 100029, China.
² University of the Chinese Academy of Sciences, Beijing 100049, China.
³ Department of Functional Material Research, Central Iron and Steel Research Institute, Beijing 100081, China.
⁴ School of Microelectronics, University of Science and Technology of China, Hefei 230026, China.
⁵ State Key Laboratory of ASIC and System, School of Microelectronics, Fudan University, Shanghai 201203, China.

Abstract

Two-dimensional van der Waals (2D vdW) ferromagnets possess outstanding scalability, controllable ferromagnetism, and out-of-plane anisotropy, enabling the compact spintronics-based non-volatile in-memory computing (nv-IMC) that promises to tackle the memory wall bottleneck issue. Here, by employing the intriguing room-temperature ferromagnetic characteristics of emerging 2D Fe₃GeTe₂ with the dissimilar electronic structure of the two spin-conducting channels, we report on a new type of non-volatile spin-orbit torque (SOT) magnetic tunnel junction (MTJ) device based on Fe₃GeTe₂/MgO/Fe₃GeTe₂ heterostructure, which demonstrates the uni-polar and high-speed field-free magnetization switching by adjusting the ratio of field-like torque to damping-like torque coefficient in the free layer. Compared to the conventional 2T1M structure, the developed 3-transistor-2-MTJ (3T2M) cell is implemented with the complementary data storage feature and the enhanced sensing margin of 201.4% (from 271.7 mV to 547.2 mV) and 276% (from 188.2 mV to 520 mV) for reading "1" and "0", respectively. Moreover, superior to the traditional CoFeB-based MTJ memory cell counterpart, the 3T2M crossbar array architecture can be executed for AND/NAND, OR/NOR Boolean logic operation with a fast latency of 24 ps and ultra-low power consumption of 2.47 fJ/bit. Such device to architecture design with elaborated micro-magnetic and circuit-level simulation results shows great potential for realizing high-performance 2D material-based compact SOT magnetic random-access memory, facilitating new applications of highly reliable and energy-efficient nv-IMC.

Keywords: Fe3GeTe2; field-free magnetization switching; magnetoresistive random-access memory; non-volatile in-memory computing; spin-orbit torque.

Abstract

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