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Monolayer MoS2 Bandgap Modulation by Dielectric Environments and Tunable Bandgap Transistors.

ABSTRACT: Semiconductors with a moderate bandgap have enabled modern electronic device technology, and the current scaling trends down to nanometer scale have introduced two-dimensional (2D) semiconductors. The bandgap of a semiconductor has been an intrinsic property independent of the environments and determined fundamental semiconductor device characteristics. In contrast to bulk semiconductors, we demonstrate that an atomically thin two-dimensional semiconductor has a bandgap with strong dependence on dielectric environments. Specifically, monolayer MoS2 bandgap is shown to change from 2.8?eV to 1.9?eV by dielectric environment. Utilizing the bandgap modulation property, a tunable bandgap transistor, which can be in general made of a two-dimensional semiconductor, is proposed.

SUBMITTER: Ryou J

PROVIDER: S-EPMC4932597 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Monolayer MoS2 Bandgap Modulation by Dielectric Environments and Tunable Bandgap Transistors.

Ryou Junga J Kim Yong-Sung YS Kc Santosh S Cho Kyeongjae K

Scientific reports 20160705

Semiconductors with a moderate bandgap have enabled modern electronic device technology, and the current scaling trends down to nanometer scale have introduced two-dimensional (2D) semiconductors. The bandgap of a semiconductor has been an intrinsic property independent of the environments and determined fundamental semiconductor device characteristics. In contrast to bulk semiconductors, we demonstrate that an atomically thin two-dimensional semiconductor has a bandgap with strong dependence on ...[more]

PMID: 27378032

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