Hydrogen Plasma Exposure of Monolayer MoS2 Field-Effect Transistors and Prevention of Desulfurization by Monolayer Graphene

Autor:	Tiantian Li, Madan Dubey, Tingyi Gu, Anishkumar Soman, Robert A. Burke, Michael D. Valentin, Dun Mao, Qiu Li
Rok vydání:	2020
Předmět:	Electron mobility Materials science business.industry Carrier scattering Vacancy defect Schottky barrier Monolayer Optoelectronics General Materials Science Wafer Field-effect transistor Chemical vapor deposition business
Zdroj:	ACS Applied Materials & Interfaces. 12:37305-37312
ISSN:	1944-8252 1944-8244
DOI:	10.1021/acsami.0c07818
Popis:	Atomic vacancies related to structural disorder and doping variation influence carrier transport in monolayer transition-metal dichalcogenide devices. Here, we investigate the effect of hydrogen plasma exposure (HPE) on monolayer MoS2 field-effect transistors (FETs). We observe that a 1% increase in sulfur vacancy after HPE results in incremental 0.06 eV of the Schottky barrier. Short-range scattering from the sulfur vacancies reduces the carrier mobility of monolayer MoS2 by 2 orders of magnitude. Despite the defects and grain boundaries formed during the chemical vapor deposition and transferring process, the surface desulfurization induced by the proton exposure and thermally accelerated oxidation can be blocked by monolayer graphene cladding with a van der Waals contact distance of 2.5 A. The material-level study indicates a promising route for a low-cost and robust fabrication of smart sensor circuits on a monolithic MoS2 wafer, where the bare MoS2 FETs can serve as proton sensors, with their electronic readout processed by a logic circuit of graphene-protected pristine FETs with a high on/off ratio.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::5ddcd0354a4f128c59e72f97887d4322 https://doi.org/10.1021/acsami.0c07818 Zobrazit plný text záznamu