April 7 - 11, 2025
Seattle, Washington
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2025 MRS Spring Meeting & Exhibit
EL03.08.10

Integrated 1D epitaxial mirror twin boundaries for ultra-scaled 2D MoS2 field-effect transistor

When and Where

Apr 9, 2025
5:00pm - 7:00pm
Summit, Level 2, Flex Hall C

Presenter(s)

Co-Author(s)

Hyun Je Cho1,2,Gunho Moon1,2,Heonsu Ahn1,2,Moon-Ho Jo2,1

Pohang University of Science and Technology1,Institute for Basic Science2

Abstract

Hyun Je Cho1,2,Gunho Moon1,2,Heonsu Ahn1,2,Moon-Ho Jo2,1

Pohang University of Science and Technology1,Institute for Basic Science2
In atomically thin van der Waals materials, grain boundaries (GBs) – the line defects between adjacent crystal grains with tilted in-plane rotations – are omnipresent. When the tilting angles are arbitrary, the GBs form inhomogeneous sublattices, giving rise to local electronic states that are not controlled. Here, we report epitaxial realizations of deterministic MoS2 mirror 44 twin boundaries (MTBs), at which two adjoining crystals are reflection-mirroring by the exact 60° rotation by position-controlled epitaxy. We showed that these epitaxial MTBs are one-dimensionally (1D) metallic to a circuit length scale. By utilizing the ultimate 1D feature (the width of ~0.4 nanometre and the length up to a few tens of micrometre), we incorporated the epitaxial MTBs as the 1D gate to build integrated two-dimensional (2D) field-effect transistors (FETs). The critical role of the 1D MTB gate was verified to scale the depletion channel length down to 3.9 nm, resulting in the substantially lowered channel off-current at lower gate voltages. With that, in both individual and array FETs, we demonstrated the state-of-the-art performances for low power logics. 1D epitaxial MTB gates in this work suggest a novel synthetic pathway for integration of 2D FETs – that are immune to high gate capacitance – toward ultimate scaling.

Keywords

2D materials | grain boundaries

Symposium Organizers

Eli Sutter, University of Nebraska--Lincoln
Luca Camilli, University of Rome Tor Vergata
Mads Brandbyge, Technical University of Denmark
José Manuel Caridad Hernández, Universidad de Salamanca

Session Chairs

Mads Brandbyge
Luca Camilli

In this Session