Nonvolatile Multistates Memories for High-Density Data Storage

Abstract

In the current information age, the realization of memory devices with energy efficient design, high storage density, nonvolatility, fast access, and low cost is still a great challenge. As a promising technology to meet these stringent requirements, nonvolatile multistates memory (NMSM) has attracted lots of attention over the past years. Owing to the capability to store data in more than a single bit (0 or 1), the storage density is dramatically enhanced without scaling down the memory cell, making memory devices more efficient and less expensive. Multistates in a single cell also provide an unconventional in-memory computing platform beyond the Von Neumann architecture and enable neuromorphic computing with low power consumption. In this review, an in-depth perspective is presented on the recent progress and challenges on the device architectures, material innovation, working mechanisms of various types of NMSMs, including flash, magnetic random-access memory (MRAM), resistive random-access memory (RRAM), ferroelectric random-access memory (FeRAM), and phase-change memory (PCM). The intriguing properties and performance of these NMSMs, which are the key to realizing highly integrated memory hierarchy, are discussed and compared.

Coupled Current Jumps and Domain Wall Creeps in a Defect‐Engineered Ferroelectric Resistive Memory

“…This drives the development of emerging non‐volatile memories with more functionalities and better performance, such as phase‐change memory, [ 1 ] resistive random‐access memory (RRAM), [ 2 ] magnetic random‐access memory (MRAM), [ 3 ] and ferroelectric (FE) random‐access memory (FRAM). [ 4,5 ] Traditional FRAM is based on the FE capacitor that utilizes the polarization charge to store information, reading of which is a destructive process, and a re‐writing process by electric field larger than coercivity is required to restore the information. This makes it difficult for size‐scaling and hinders its widespread application.…”

Stimuli‐Responsive Memristive Materials for Artificial Synapses and Neuromorphic Computing

“…On the other hand, devices that utilize domain wall motion can have multiple stable intermediate states within one device. [ 148 ] Wang et al. demonstrated memristive phenomena in both thin‐film elements and spin valves with domain wall motions.…”

Correlative imaging of ferroelectric domain walls

“…Technological advances rely heavily on the development of new materials, both in terms of understanding their fundamental properties and through the engineering of their composition and structure. In the last decades, complex oxide materials have shown promise in photovoltaics applications 1 , high efficiency actuation and sensing 2 , as well as information storage 3 . Among these materials, ferroelectrics are of particular interest.…”