Memtransistor Devices Based on MoS₂Multilayers with Volatile Switching due to Ag Cation Migration

Abstract

In the recent years, the need for fast, robust, and scalable memory devices have spurred the exploration of advanced materials with unique electrical properties. Among these materials, 2D semiconductors are promising candidates as they combine atomically thin size, semiconductor behavior, and complementary metal–oxide‐semiconductor compatibility. Here a three‐terminal memtransistor device, based on multilayer MoS2 with ultrashort channel length, that combines the usual transistor behavior of 2D semiconductors with resistive switching memory operation is presented. The volatile switching behavior is explained by the Ag cation migration along the channel surface. An extensive physical and electrical characterization to investigate the fundamental properties of the device, is presented. Finally, a chain‐type memory array architecture similar to a NAND flash structure consisting of memtransistors is demonstrated, where the individual memory devices can be selected for write and read, paving the way for high‐density, 3D memories based on 2D semiconductors.

Novel charm of 2D materials engineering in memristor: when electronics encounter layered morphology

“…Long-term potentiation and depression in MoS 2 memtransistors imitated excitatory and inhibitory synapses in organisms. Farronato et al 196 presented a memtransistor device based on multilayer MoS 2 with an ultrashort channel length. The device had transistor characteristics with a high resistance ratio between LRS and HRS and a memristive switching characteristic at source–drain voltages around 0.8 V. Finally, the potential of the memtransistor device was exhibited with a chain-type memory array design displaying select/unselect properties during the program and read operations.…”

Forming‐Free Resistive Switching Memory Crosspoint Arrays for In‐Memory Machine Learning

“…RRAM is a two-terminal device where the conductance can be manipulated by externally applied voltage pulses. [1][2][3][4][5][6][7][8][9][10] The RRAM switching mechanism can be explained by the oxide layer being capable of locally changing the oxygen vacancy concentration. [20,21] Metals with high work function (such as Pt or TiN) are usually adopted as Schottky-type bottom electrode materials as they are inert with respect to the oxide interface.…”

“…[1][2][3][4] In-memory computing (IMC) appears as one of the most promising candidates to improve the performance and energy efficiency of computation, thanks to its suppressed data movement and inherent parallelism. Emerging memory technologies, such as the resistive switching memory (RRAM), [1][2][3][4] the phase-change memory (PCM), [3] and 2D materials-based memristors [5] and memtransistors, [6] allow for unique features, such as analogue programmability, good scaling, and back-end-of-line integration, which can strongly support the development of scalable, energy efficient IMC systems. Among the various emerging memories, RRAM appears as one of the most promising technologies for IMC, thanks to the CMOS-compatible fabrication process, [7] the small area, [8] and the analog programming.…”

“…[7,10,11] However it is a slow and energyconsuming task for CMOS-based digital computers. [1][2][3][4][5][6]12] On the other hand, emerging memories can execute MVM in parallel within the crosspoint array, by summing the currents according to Kirchhoff 's law and multiplying voltage and conductance by Ohm's law. [12,13] The principal component analysis (PCA), for instance, which is a key algorithm in machine learning and data analytics, strongly relies on MVM for extracting the eigenvector of the covariance matrix.…”

Physical Insights into Vacancy-Based Memtransistors: Toward Power Efficiency, Reliable Operation, and Scalability

“…14 Significant advances in the experimental demonstration of 2DMat-based memtransistors that include a six-terminal chemical vapor deposition (CVD)grown MoS 2 memtransistor, 7 a monolayer MoS 2 memtransis- tor with site-specific defects, 15 and a GaSe-based threeterminal memtransistor 16 have been reported. More recently, ion-based memtransistors involving Ag cation migration dynamics in MoS 2 multilayers 17 and their utility as a 2D artificial neuron 18 have also been explored. However, the study of the interaction between different types of the dominant carrier-type (electron vs holes) with charged defects and its impact on the RS behavior is still lacking, as all prior works focused solely on the unipolar conduction in memtransistor.…”