Strain effect engineered in {\alpha}-Al2O3/monolayer MoS2 interface by first principle calculations

TL;DR

This study uses first-principles calculations to show how Al2O3 dielectric layers induce strain in monolayer MoS2, revealing a method to engineer strain effects in 2D material interfaces for nanotechnology applications.

Contribution

It demonstrates that dielectric layer thickness and temperature can be used to control strain in MoS2 via interface engineering, a novel approach for strain manipulation.

Findings

Al2O3 induces up to 0.3% strain on MoS2 monolayer

Strain increases with dielectric thickness

Higher temperature causes lattice expansion

Abstract

With the advances in low dimensional transition metal dichalcolgenides (TMDCs) based metal oxide semiconductor field effect transistor (MOSFET), the interface between semiconductors and dielectrics has received considerable attention due to its dramatic effects on the morphology and charge transport of semiconductors. In this study, first principle calculations were utilized to investigate the strain effect induced by the interface between Al2O3 (0001) and monolayer MoS2. The results indicate that Al2O3 in 1.3nm thickness can apply the strain of 0.3% on MoS2 monolayer. The strain effect monotonically increases with the larger thickness of the dielectric layer. Also, the study on temperature effect indicates the monotonic lattice expansion induced by the higher temperature. Our study proposes that the dielectric engineering can be an effective tool for strain effect in the nanotechnology.