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Hole doping effect of MoS₂ via electron capture of He⁺ ion irradiation.

ABSTRACT: Beyond the general purpose of noble gas ion sputtering, which is to achieve functional defect engineering of two-dimensional (2D) materials, we herein report another positive effect of low-energy (100 eV) He⁺ ion irradiation: converting n-type MoS₂ to p-type by electron capture through the migration of the topmost S atoms. The electron capture ability via He⁺ ion irradiation is valid for supported bilayer MoS₂; however, it is limited at supported monolayer MoS₂ because the charges on the underlying substrates transfer into the monolayer under the current condition for He⁺ ion irradiation. Our technique provides a stable and universal method for converting n-type 2D transition metal dichalcogenides (TMDs) into p-type semiconductors in a controlled fashion using low-energy He⁺ ion irradiation.

SUBMITTER: Han SW

PROVIDER: S-EPMC8654839 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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Hole doping effect of MoS2 via electron capture of He+ ion irradiation.

Han Sang Wook SW Yun Won Seok WS Kim Hyesun H Kim Yanghee Y Kim D-H DH Ahn Chang Won CW Ryu Sunmin S

Scientific reports 20211208 1

Beyond the general purpose of noble gas ion sputtering, which is to achieve functional defect engineering of two-dimensional (2D) materials, we herein report another positive effect of low-energy (100 eV) He+ ion irradiation: converting n-type MoS2 to p-type by electron capture through the migration of the topmost S atoms. The electron capture ability via He+ ion irradiation is valid for supported bilayer MoS2; however, it is limited at supported monol ...[more]

PMID: 34880289

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