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MoS2 Heterojunctions by Thickness Modulation.

ABSTRACT: In this work, we report lateral heterojunction formation in as-exfoliated MoS2 flakes by thickness modulation. Kelvin probe force microscopy is used to map the surface potential at the monolayer-multilayer heterojunction, and consequently the conduction band offset is extracted. Scanning photocurrent microscopy is performed to investigate the spatial photocurrent response along the length of the device including the source and the drain contacts as well as the monolayer-multilayer junction. The peak photocurrent is measured at the monolayer-multilayer interface, which is attributed to the formation of a type-I heterojunction. The work presents experimental and theoretical understanding of the band alignment and photoresponse of thickness modulated MoS2 junctions with important implications for exploring novel optoelectronic devices.

SUBMITTER: Tosun M

PROVIDER: S-EPMC4485222 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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MoS2 Heterojunctions by Thickness Modulation.

Tosun Mahmut M Fu Deyi D Desai Sujay B SB Ko Changhyun C Kang Jeong Seuk JS Lien Der-Hsien DH Najmzadeh Mohammad M Tongay Sefaattin S Wu Junqiao J Javey Ali A

Scientific reports 20150630

In this work, we report lateral heterojunction formation in as-exfoliated MoS2 flakes by thickness modulation. Kelvin probe force microscopy is used to map the surface potential at the monolayer-multilayer heterojunction, and consequently the conduction band offset is extracted. Scanning photocurrent microscopy is performed to investigate the spatial photocurrent response along the length of the device including the source and the drain contacts as well as the monolayer-multilayer junction. The ...[more]

PMID: 26121940

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