Modulation of Heavy Metal/Ferromagnetic Metal Interface for High‐Performance Spintronic Devices

Abstract

Spintronic devices such as magnetic tunnel junctions and skyrmions have attracted considerable attention due to features such as nonvolatility, high scalability, low power, and high speed. Over the past few years, innovative materials and new structures in this field have resulted in the emergence of new phenomena and exciting device performance. It has been found that the heavy metal (HM)/ferromagnetic metal (FM) interface plays an essential role in spintronic devices. Spintronic device performance can be significantly enhanced through proper modulation of this interface. Recent progress in this blooming field is reviewed with specific emphasis on the HM/FM interface. Investigations into HM/FM-interface-related phenomena, including perpendicular magnetic anisotropy, tunnel magnetoresistance, magnetic damping, spin-orbit torque, and Dzyaloshinskii-Moriya interaction, are put into context. Guidelines for realizing high-performance spintronic devices are provided, and an outlook on their future research direction and potential applications is given.

Origin of the large interfacial perpendicular magnetic anisotropy in MgO/Co2FeAl

“…1,2 In particular, the perpendicular MTJs (p-MTJs) that possessed perpendicular magnetic anisotropy (PMA) have attracted great attention in recent years because of their promising applications in the next-generation spintronic devices towards using faster and smaller magnetic bits. [3][4][5][6] In p-MTJs, PMA occurs at the interface between ferromagnetic thin film and insulating barrier and its strength is characterized by the magnetic anisotropy constant (K i ), which is defined as the anisotropy energy per unit area. 7 To achieve a high thermal stability of the relative magnetization orientation of the two ferromagnetic electrodes, a large K i is desired.…”

Enhancing domain wall velocity through interface intermixing in W-CoFeB-MgO films with perpendicular anisotropy

“…This direct relationship between the relative variation of DMI and interface anisotropy upon intermixing indicates that they have the same origin, the exchange interaction between magnetic and heavy metal atoms mediated by spin-orbit coupling. [35][36][37] In summary, we have studied the influence of He þ irradiationinduced interfacial intermixing on domain wall dynamics and Dzyaloshinskii-Moriya interaction. We have observed a large increase in domain wall velocity in the creep regime which is consistent with a reduction of pinning at the W/CoFeB interface.…”

A Survey of Test and Reliability Solutions for Magnetic Random Access Memories

“…Plasma oxidation was proved to be an effective method to produce Al-metal-based MTJ with ultrauniform resistance [110]. Interface engineering is another efficient way to improve the write and read reliability [111]. The performance of MTJs can be significantly enhanced through proper modulation of heavy metal/FM metal interface, such as perpendicular magnetic anisotropy, TMR, and magnetic damping.…”