Pressurizing Field-Effect Transistors of Few-Layer MoS2 in a Diamond Anvil Cell

TL;DR

This paper demonstrates a novel method to study few-layer MoS2 FETs under high pressure in a diamond anvil cell, revealing enhanced electronic properties and enabling exploration of new material phases.

Contribution

It introduces a feasible approach to fabricate and measure FETs in a DAC, combining pressure and electric field tuning for the first time.

Findings

MoS2 FET mobility increases under pressure

Conductance and carrier concentration are significantly enhanced

Method enables exploration of new material phases

Abstract

Hydrostatic pressure applied using diamond anvil cells (DAC) has been widely explored to modulate physical properties of materials by tuning their lattice degree of freedom. Independently, electrical field is able to tune the electronic degree of freedom of functional materials via, for example, the field-effect transistor (FET) configuration. Combining these two orthogonal approaches would allow discovery of new physical properties and phases going beyond the known phase space. Such experiments are, however, technically challenging and have not been demonstrated. Herein, we report a feasible strategy to prepare and measure FETs in a DAC by lithographically patterning the nanodevices onto the diamond culet. Multiple-terminal FETs were fabricated in the DAC using few-layer MoS2 and BN as the channel semiconductor and dielectric layer, respectively. It is found that the mobility, conductance, carrier concentration, and contact conductance of MoS2 can all be significantly enhanced with pressure. We expect that the approach could enable unprecedented ways to explore new phases and properties of materials under coupled mechano-electrostatic modulation.