Tunnel Junction with Perpendicular Magnetic Anisotropy: Status and Challenges

Abstract

Magnetic tunnel junction (MTJ), which arises from emerging spintronics, has the potential to become the basic component of novel memory, logic circuits, and other applications. Particularly since the first demonstration of current induced magnetization switching in MTJ, spin transfer torque magnetic random access memory (STT-MRAM) has sparked a huge interest thanks to its non-volatility, fast access speed, and infinite endurance. However, along with the advanced nodes scaling, MTJ with in-plane magnetic anisotropy suffers from modest thermal stability, high power consumption, and manufactural challenges. To address these concerns, focus of research has converted to the preferable perpendicular magnetic anisotropy (PMA) based MTJ, whereas a number of conditions still have to be met before its practical application. This paper overviews the principles of PMA and STT, where relevant issues are preliminarily discussed. Centering on the interfacial PMA in CoFeB/MgO system, we present the fundamentals and latest progress in the engineering, material, and structural points of view. The last part illustrates potential investigations and applications with regard to MTJ with interfacial PMA.

Energy and Performance Benchmarking of a Domain Wall-Magnetic Tunnel Junction Multibit Adder

“…The switching current requirements of our device, important for energy efficiency, are notably set by the style of anisotropy in our output MTJ. For all the following simulations, we have assumed that the device has perpendicular magnetic anisotropy (PMA), which typically has a lower energy barrier and thus a reduced switching current compared with in-plane magnetic anisotropy (IMA) [25]. Table 1 lists the parameters used for the comparison of DW-MTJ logic with the 2018 CMOS technology node of the International Technology Roadmap for Semiconductors [26], which assumes a metal-1 half pitch of 15 nm.…”

Tunable Memristic Characteristics Based on Graphene Oxide Charge-Trap Memory

“…It can revolutionize the product performance in digital memories, particularly capable of substituting all current up-to-date memories like hard disk drives, random-access memories, and Flash memories. Among all the technology candidates, memristor-based ReRAM operates faster than phase change random access memory (PCRAM), and it possesses not a simpler, but a smaller cell structure than magnetic random access memory (MRAM) or shared transistor technology random access memory (STT-RAM) [ 3 , 4 , 5 ]. Confronted with a traditional Metal-Oxide-Semiconductor (MOS)-accessed memory cell, memristor-based RRAM bears the promising potential of forming a cross-point structure without access devices, for the sake of achieving an ultra-high density form of data storage.…”

From MTJ Device to Hybrid CMOS/MTJ Circuits: A Review

“…TDDB is a mechanism to determine the MTJ lifetime and depends on the polarity of applied voltage, thickness variations, and other process induced damages [189]. pMTJ having an oxide barrier of size less than 1 nm designed to transmit a high-density spinpolarized current (>1 MA/cm 2 ) can cause dielectric breakdown due to self-heating, which can generate a functional error in the hybrid CMOS/MTJ circuits [117,190]. Wang et al proposed a compact model of MTJ by incorporating the phenomena of dielectric breakdown of the MgO barrier with STT stochastic behavior in which technical variations and temperature evaluation are integrated [36].…”