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Photoresponse of graphene field-effect-transistor with n-type Si depletion layer gate.

ABSTRACT: Graphene/semiconductor Schottky junctions are an emerging field for high-performance optoelectronic devices. This study investigates not only the steady state but also the transient photoresponse of graphene field-effect transistor (G-FET) of which gate bias is applied through the Schottky barrier formed at an n-type Si/graphene interface with a thin oxide layer, where the oxide thickness is sufficiently thin for tunneling of the charge carrier. To analyze the photoresponse, we formulate the charge accumulation process at the n-Si/graphene interface, where the tunneling process through the SiO_x layer to graphene occurs along with recombination of the accumulated holes and the electrons in the graphene at the surface states on the SiO_x layer. Numerical calculations show good qualitative agreement with the experimentally obtained results for the photoresponse of G-FET.

SUBMITTER: Kobayashi S

PROVIDER: S-EPMC5859296 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Photoresponse of graphene field-effect-transistor with n-type Si depletion layer gate.

Kobayashi Shiho S Anno Yuki Y Takei Kuniharu K Arie Takayuki T Akita Seiji S

Scientific reports 20180319 1

Graphene/semiconductor Schottky junctions are an emerging field for high-performance optoelectronic devices. This study investigates not only the steady state but also the transient photoresponse of graphene field-effect transistor (G-FET) of which gate bias is applied through the Schottky barrier formed at an n-type Si/graphene interface with a thin oxide layer, where the oxide thickness is sufficiently thin for tunneling of the charge carrier. To analyze the photoresponse, we formulate the cha ...[more]

PMID: 29556066

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