An Atomically Resolved Schottky Barrier Height Approach for Bridging the Gap between Theory and Experiment at Metal–Semiconductor Heterojunctions

An Atomically Resolved Schottky Barrier Height Approach for Bridging the Gap between Theory and Experiment at Metal–Semiconductor Heterojunctions

ACS Applied Materials & Interfaces

10.1021/acsami.4c02294

https://pubs.acs.org/doi/10.1021/acsami.4c02294

Viacheslav Sorkin, Hangbo Zhou, Zhi Gen Yu, Kah-Wee Ang, Yong-Wei Zhang

General Materials Science

22 April 2024

Viacheslav Sorkin, Hangbo Zhou, Zhi Gen Yu, Kah-Wee Ang, and Yong-Wei Zhang. (2024). An Atomically Resolved Schottky Barrier Height Approach for Bridging the Gap between Theory and Experiment at Metal–Semiconductor Heterojunctions. ACS Applied Materials & Interfaces,16 (17), 22166-22176. DOI: 10.1021/acsami.4c02294

We propose an atomically resolved approach to capture the spatial variations of the Schottky barrier height (SBH) at metal–semiconductor heterojunctions. This proposed scheme, based on atom-specific partial density of states (PDOS) calculations, further enables calculation of the effective SBH that aligns with conductance measurements. We apply this approach to study the variations of SBH at MoS2@Au heterojunctions, in which MoS2 contains conducting and semiconducting grain boundaries (GBs). Our results reveal that there are significant variations in SBH at atoms in the defected heterojunctions. Of particular interest is the fact that the SBH in some areas with extended defects approaches zero, indicating Ohmic contact. One important implication of this finding is that the effective SBH should be intrinsically dependent on the defect density and character. Remarkably, the obtained effective SBH values demonstrate good agreement with existing experimental measurements. Thus, the present study addresses two long-standing challenges associated with SBH in MoS2–metal heterojunctions: the wide variation in experimentally measured SBH values at MoS2@metal heterojunctions and the large discrepancy between density-functional-theory-predicted and experimentally measured SBH values. Our proposed approach points out a valuable pathway for understanding and manipulating SBHs at metal–semiconductor heterojunctions.

Publisher Copyright

This research / project is supported by the National Research Foundation - Competitive Research Programme
Grant Reference no. : NRF-CRP24-2020-0002

This research / project is supported by the Agency for Science, Technology and Research, Science and Engineering Research Council - Central Research Fund
Grant Reference no. :

This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Applied Materials & Interfaces, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see 10.1021/acsami.4c02294.

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