Efficiency Enhancement in Spin-Orbit Torque MRAM With Low Resistivity and High Spin Hall Angle in Ta/Pt Multilayer Channel

Abstract

Spin-orbit torque (SOT) is a phenomenon where spin current, generated by applying charge current to heavy metals (HMs) with strong spin-orbit coupling (SOC), is used to control the magnetization of a ferromagnetic (FM) layer. In this study, we investigate the SOT properties and power consumption of Ta/Pt multilayered SOT channel devices. By varying the Pt concentration in the Ta channel, the spin Hall angle transitions from negative (Ta-like) to positive (Pt-like), with Ta20Pt80 achieving an 18% increase in spin Hall angle compared to pure Ta. Furthermore, as the Pt concentration increases, the resistivity of the channel decreases, leading to improved power consumption efficiency. Finally, we analyze the overall power consumption efficiency of the channel material, considering both resistivity and spin Hall angle. The result is that the power consumption of Ta20Pt80 improved by x6.1 compared to that of a pure Ta.