Physics of electron emission and injection in two‐dimensional materials: Theory and simulation

Abstract

Electrically contacting two‐dimensional (2D) materials is an inevitable process in the fabrication of devices for both the study of fundamental nanoscale charge transport physics and the design of high‐performance novel electronic and optoelectronic devices. The physics of electrical contact formation and interfacial charge injection critically underlies the performance, energy‐efficiency and the functionality of 2D‐material‐based devices, thus representing one of the key factors in determining whether 2D materials can be successfully implemented as a new material basis for the development of next‐generation beyond‐silicon solid‐state device technology. In this review, the recent developments in the theory and the computational simulation of electron emission, interfacial charge injection and electrical contact formation in 2D material interfaces, heterostructures, and devices are reviewed. Focusing on thermionic charge injection phenomena which are omnipresent in 2D‐materials‐based metal/semiconductor Schottky contacts, we summarize various transport models and scaling laws recently developed for 2D materials. Recent progress on the first‐principle density functional theory simulation of 2D‐material‐based electrical contacts are also reviewed. This review aims to provide a crystalized summary on the physics of charge injection in the 2D Flatlands for bridging the theoretical and the experimental research communities of 2D material device physics and technology.

Recent Progress on Two-Dimensional Materials

“…materials With many unique electronic and optoelectronic properties 768,769 , 2D materials are promising for emerging computing technologies. In this section, we will provide a brief overview of recent progress in 2D material-based logic circuits, neuromorphic computing.…”

ROS‐Catalytic Transition‐Metal‐Based Enzymatic Nanoagents for Tumor and Bacterial Eradication

“…TMDs, another typical of emerged 2D materials, have attracted massive attention in recent years. [105] Due to their tunable morphology, active sites, and unique electronic structures, both surface and edges of TMDs can be functionalized to achieve specific catalytic sites for different applications, such as biosensing, antitumor, and bacterial disinfection. [106,107] For example, MoS 2 has been discovered with PODlike activity, which was further used in biodetecting for H 2 O 2 XPS spectrum of PEG/Fe-LDHs, respectively.…”

Low‐Energy Oxygen Plasma Injection of 2D Bi2Se3 Realizes Highly Controllable Resistive Random Access Memory

“…Subsequently, the influence of the injection time on the RS is investigated through comparative experiments with the same injection power of 100 W. As the injection time rises from 30 s (Figure S9d,e, Supporting Information) to 60 s (Figure S10a,b, Supporting Information), the conduction mechanism of the HRS is converted from SCLC to SE (ln(I)∝V 1/2 ). [39][40][41] The sufficient formation of oxides results in that the leading role of intrinsic charge traps is replaced by SE formed under the contact between metal and oxide. However, the LRS process still conforms to Ohmic conductivity, so that the biggest memory window is achieved.…”