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Room Temperature Negative Differential Resistance with High Peak Current in MoS₂/WSe₂ Heterostructures.

ABSTRACT: Two-dimensional transition metal dichalcogenide (2D TMD) semiconductors allow facile integration of p- and n-type materials without a lattice mismatch. Here, we demonstrate gate-tunable n- and p-type junctions based on vertical heterostructures of MoS₂ and WSe₂ using van der Waals (vdW) contacts. The p-n junction shows negative differential resistance (NDR) due to Fowler-Nordheim (F-N) tunneling through the triangular barrier formed by applying a global back-gate bias (V_GS). We also show that the integration of hexagonal boron nitride (h-BN) as an insulating tunnel barrier between MoS₂ and WSe₂ leads to the formation of sharp band edges and unintentional inelastic tunnelling current. The devices based on vdW contacts, global V_GS, and h-BN tunnel barriers exhibit NDR with a peak current (I_peak) of 315 μA, suggesting that the approach may be useful for applications.

SUBMITTER: Kim JH

PROVIDER: S-EPMC10906070 | biostudies-literature | 2024 Feb

REPOSITORIES: biostudies-literature

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Room Temperature Negative Differential Resistance with High Peak Current in MoS2/WSe2 Heterostructures.

Kim Jung Ho JH Sarkar Soumya S Wang Yan Y Taniguchi Takashi T Watanabe Kenji K Chhowalla Manish M

Nano letters 20240216 8

Two-dimensional transition metal dichalcogenide (2D TMD) semiconductors allow facile integration of p- and n-type materials without a lattice mismatch. Here, we demonstrate gate-tunable n- and p-type junctions based on vertical heterostructures of MoS2 and WSe2 using van der Waals (vdW) contacts. The p-n junction shows negative differential resistance (NDR) due to Fowler-Nordheim (F-N) tunneling through the triangular barrier formed by applying a global back-gate bias (V ...[more]

PMID: 38363877

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