Strain-engineering the Schottky barrier and electrical transport on MoS2

Abstract

Strain provides an effective means to tune the electrical properties while retaining the native chemical composition of the material. Unlike three-dimensional solids, two-dimensional materials withstand higher levels of elastic strain making it easier to tune various electrical properties to suit the technology needs. In this work we explore the effect of uniaxial tensile-strain on the electrical transport properties of bi- and few-layered MoS2, a promising 2D semiconductor. Raman shifts corresponding to the in-plane vibrational modes show a redshift with strain indicating a softening of the in-plane phonon modes. Photo luminescence measurements reveal a redshift in the direct and the indirect emission peaks signalling a reduction in the material bandgap. Transport measurements show a substantial enhancement in the electrical conductivity with a high piezoresistive gauge factor of ~ 321 superior to that for Silicon for our bi-layered device. The simulations conducted over the experimental findings reveal a substantial reduction of the Schottky barrier height at the electrical contacts in addition to the resistance of MoS2. Our studies reveal that strain is an important and versatile ingredient to tune the electrical properties of 2D materials and also can be used to engineer high-efficiency electrical contacts for future device engineering.

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Cited by in corpus (11)

• Strain-Enhanced Mobility of Monolayer MoS2
• Strain engineering in single-, bi- and tri-layer MoS2, MoSe2, WS2 and WSe2
• Biaxial versus uniaxial strain tuning of single-layer MoS${}_2$
• CMOS-compatible Strain Engineering for High-Performance Monolayer Semiconductor Transistors
• Biaxial Tensile Strain Enhances Electron Mobility of Monolayer Transition Metal Dichalcogenides
• Giant piezoresistive effect and strong band gap tunability in ultrathin InSe upon biaxial strain
• Nonlocal Exciton-Photon Interactions in Hybrid High-Q Beam Nanocavities with Encapsulated MoS${}_2$ Monolayers
• Strain Induced Modulation of Local Transport of 2D Materials at the Nanoscale
• Statistical Analysis of Contacts to Synthetic Monolayer MoS2
• Enhanced Strain Transfer and Optoelectronic Performance in MoS2 Devices via Formvar Encapsulation
• Uniaxial Strain-Induced Electronic Properties Alteration of MoS${}_2$ Monolayer