Quantum Transport in Two-Dimensional WS${}_2$ with High-Efficiency Carrier Injection Through Indium Alloy Contacts

Abstract

Two-dimensional transition metal dichalcogenides (TMDCs) have properties attractive for optoelectronic and quantum applications. A crucial element for devices is the metal-semiconductor interface. However, high contact resistances have hindered progress. Quantum transport studies are scant as low-quality contacts are intractable at cryogenic temperatures. Here, temperature-dependent transfer length measurements are performed on chemical vapour deposition grown single-layer and bilayer WS${}_2$ devices with indium alloy contacts. The devices exhibit low contact resistances and Schottky barrier heights (\sim10 k$\Omega$\si{\micro\metre} at 3 K and 1.7 meV). Efficient carrier injection enables high carrier mobilities ($\sim$190 cm${}^2$V${}^{-1}$s${}^{-1}$) and observation of resonant tunnelling. Density functional theory calculations provide insights into quantum transport and properties of the WS${}_2$-indium interface. Our results reveal significant advances towards high-performance WS${}_2$ devices using indium alloy contacts.

5 Figures

References in corpus (15)

• Atomically thin MoS2: A new direct-gap semiconductor
• Mobility engineering and metal-insulator transition in monolayer MoS2
• The Nature of Electronic States in Atomically Thin MoS2 Field-Effect Transistors
• Two dimensional semiconductors with possible high room temperature mobility
• Electrical Transport Properties of Single-Layer WS2
• Improved Contacts to MoS2 Transistors by Ultra-High Vacuum Metal Deposition
• Mono- and Bilayer WS2 Light-Emitting Transistors
• Towards barrier free contact to MoS2 using graphene electrodes
• Spin-orbit coupling, quantum dots, and qubits in monolayer transition metal dichalcogenides
• Transistors with Chemically Synthesized Layered Semiconductor WS2 Exhibiting 105 Room Temperature Modulation and Ambipolar Behavior
• High-Performance Monolayer WS2 Field-effect Transistors on High-k Dielectrics
• Atomically-thin Ohmic Edge Contacts Between Two-dimensional Materials
• High Performance Field-Effect Transistor Based on Multilayer Tungsten Disulfide
• Universal low-temperature Ohmic contacts for quantum transport in transition metal dichalcogenides
• Single layer MoS2 nanoribbon field effect transistor

Cited by in corpus (3)

• Dielectrics for Two-Dimensional Transition Metal Dichalcogenide Applications
• Electrical contact properties between Yb and few-layer WS${}_2$
• Designing Efficient Metal Contacts to Two-Dimensional Semiconductors MoSi${}_2$N${}_4$ and WSi${}_2$N${}_4$ Monolayers