Selective hydrogenation improves interface properties of high-k dielectrics on 2D semiconductors

TL;DR

This paper introduces a selective hydrogenation method to enhance the interface quality between high-k dielectrics and 2D semiconductors, improving electronic properties without damaging the monolayer materials.

Contribution

It presents a novel hydrogenation strategy that selectively modifies dielectric surfaces, significantly improving interface properties for 2D semiconductor integration.

Findings

Reduced interface charge redistribution

Increased band offset at the interface

Compatible with existing fabrication processes

Abstract

The integration of high-k dielectrics with two-dimensional (2D) semiconductors is a critical step towards high-performance nanoelectronics, which however remains challenging due to high density of interface states and the damage to the monolayer 2D semiconductors. In this study, we propose a selective hydrogenation strategy to improve the interface properties while do not affect the 2D semiconductors. Using the interface of monolayer MoS2 and silicon nitride as an example, we show substantially improved interface properties for electronic applications after the interfacial hydrogenation, as evidenced by reduced inhomogeneous charge redistribution, increased band offset, and untouched electronic properties of MoS2. Interestingly, this hydrogenation process selectively occurs only at the silicon nitride surface and is compatible with the current semiconductor fabrication process. We further show that this strategy is general and applicable to other interfaces between high-k dielectrics and 2D semiconductors such as HfO2 on the monolayer MoS2. Our results demonstrate a simple yet viable way to improve the interfacial properties for integrating many high-k dielectrics on a broad range of two-dimensional transition metal disulfide semiconductors.