Analysis of the Electrical Characteristics for Compact SPICE Modelling of STT-MTJ Device with Physical Parameters Variation

• Published in: IEEE International Conference on Semiconductor Electronics, Proceedings, ICSE
• Main Author: Pai M.Y.X.; Alias N.E.; Tan M.L.P.; Hamzah A.; Wahab Y.A.; Muhamad M.
• Format: Conference paper
• Language: English
• Published: Institute of Electrical and Electronics Engineers Inc. 2024
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85206474160&doi=10.1109%2fICSE62991.2024.10681337&partnerID=40&md5=6c5af047a6a18674d0ec06e4fb579678

Spin-Transfer Torque Magnetoresistive Random Access Memory (STT-MRAM) operates on the principle of magnetic anisotropy energy to retain information and magnetoresistance to retrieve information. STT-MRAM consists of an MTJ (Magnetic Tunnel Junction) and a transistor device. The MTJ comprises two layers of ferromagnetic metal separated by an insulator. A major concern in evaluating STT-MRAM technology is developing a scalable MTJ compact model capable of incorporating real variable effects across numerous technical nodes. Therefore, this work involves simulating the STT-MTJ device compact SPICE modeling at the device level using a SPICE subcircuit and a mathematical model to analyze the electrical characteristics. The I-V characteristics of parallel and anti-parallel orientations of the STT-MTJ are simulated. The parallel resistance (RP) and anti-parallel resistance (RAP) of the STT-MTJ device are varied from their original values to observe the I-V characteristic graph for each case. The I-V characteristics for different resistance values and variations in width and length are analyzed. It is observed that the Tunneling Magnetoresistance (TMR) increases by 230.77% when the resistance for parallel current (IP) is reduced, whereas the TMR increases by 105.56% when the resistance for anti-parallel current (IAP) is reduced. Moreover, as the width and length of the Free Layer (FL) increase (by 222.22%), the write current for the MTJ also increases by 492.55%. The parameters used in the STT-MTJ can be adjusted for different MTJ materials to achieve higher performance efficiency. © 2024 IEEE.