Recent Advances in the Carrier Mobility of Two-Dimensional Materials: A Theoretical Perspective

Abstract

Since the breakthrough of graphene, 2D materials have engrossed tremendous research attention due to their extraordinary properties and potential applications in electronic and optoelectronic devices. The high carrier mobility in the semiconducting material is critical to guarantee a high switching speed and low power dissipation in the corresponding device. Here, we review significant recent advances and important new developments in the carrier mobility of 2D materials based on theoretical investigations. We focus on some of the most widely studied 2D materials, their development, and future applications. Based on the current progress in this field, we conclude the review by providing challenges and an outlook in this field.

Tuning thermoelectric efficiency of monolayer indium nitride by mechanical strain

“…27,47,57,58 The other possible scattering mechanisms 59,60 (i.e., polar optical phonon scattering and intervalley scattering) are not considered due to the challenges regarding the computation of electron-phonon coupling in 2D systems. 61,62 For these reasons, our discussion is restricted with the intrinsic scattering based on the deformation potential theory, which yields an upper limit for the mobility. Thus, our reported transport coefficients are within the lower limit, which should increase when the different scattering mechanisms are taken into account.…”

Microwave Detection Using Two-Atom-Thick Self-Switching Diodes Based on Quantum Simulations and Advanced Circuit Models

“…Despite these limitations, MoS 2 has interesting properties, namely, MoS 2 monolayer is a direct bandgap n-type semiconductor, with a bandgap of about 1.9 eV, which decreases as the number of monolayers increases (its bulk counterpart being an indirect semiconductor with a bandgap of about 1.2 eV). On the other side, graphene ("the silicon of the 21st century") is a zero-gap semimetal (which can be grown with a high quality at the wafer scale) with high roomtemperature mobility (in the order of 1000 cm 2 /V • s [14]), hence suitable for detection/rectification of microwaves up to terahertz if properly patterned at the nanoscale. Hence, the combination of these two 2-D materials in their monolayer form could benefit from their individual advantages, creating a new type of device with unprecedented properties.…”

“…This type of devices has been fabricated using various semiconductor and 2-D electron gas (2DEG)-like materials, like AlGaN/GaN [6], GaN [7], InAs [5], graphene [2], [10], [11], and molybdenum disulfide (MoS 2 ) [12], [13]. Nevertheless, to the authors' knowledge, no attempt has been made so far to fabricate an SSD based on a monolayer MoS 2 /monolayer graphene heterojunction, mostly due to: 1) the difficulties in the growth of MoS 2 at the wafer scale and 2) its low mobility [14]. In this respect, this article aims at overcoming this technological gap by presenting a MoS 2 /graphene SSD on high-resistivity silicon (HRSi)/silicon dioxide substrate.…”

Scalably Nanomanufactured Atomically Thin Materials‐Based Wearable Health Sensors

“…2D semiconducting materials nevertheless suffer from intrinsically high electrical noise due to the reduced conductivity. [ 888–890,890–893 ] Achieving a co‐optimized responsivity and SNR has also been intensively pursued 2D material‐based gas sensors. [ 890–893 ] For example, to obtain an ultrahigh SNR in 2D materials‐based gas sensors, Raghu et al [ 893 ] developed a TiO 2 grafted 2D TiC nanosheets (TiO 2 /2D‐TiC)‐based ethanol gas sensor with an SNR of 18, 961, higher than the pure TiO 2 (8.3) and 2D‐TiC (339) because TiO 2 generates more surface groups for chemical adsorption of oxygen, making the TiO 2 /2D‐TiC nanosheets more sensitive to ethanol gas molecules.…”