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An Atomically Resolved Schottky Barrier Height Approach for Bridging the Gap between Theory and Experiment at
Viacheslav Sorkin1, Hangbo Zhou1, Zhi Gen Yu1
1Agency for Science, Technology and Research (A*STAR), Institute of High Performance Computing (IHPC), 1 Fusionopolis Way, #16-16 Connexis, Singapore 138632, Republic of Singapore.
ACS Applied Materials & Interfaces
|April 22, 2024
Summary
We developed a new method to precisely measure Schottky barrier height (SBH) variations at metal-semiconductor interfaces. This approach explains discrepancies in MoS2@Au heterojunctions, revealing defect-induced Ohmic contacts.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Surface Science
Background:
- Schottky barrier height (SBH) is crucial for metal-semiconductor contact performance.
- Existing methods struggle to explain experimental SBH variations in MoS2@metal heterojunctions.
- Discrepancies persist between theoretical predictions and experimental SBH measurements.
Purpose of the Study:
- To propose an atomically resolved method for calculating spatial SBH variations.
- To enable calculation of effective SBH values correlating with conductance measurements.
- To investigate SBH variations in MoS2@Au heterojunctions with grain boundaries.
Main Methods:
- Atom-specific partial density of states (PDOS) calculations.
- Application to MoS2@Au heterojunctions with conducting and semiconducting grain boundaries.
- Analysis of SBH variations at atomic scales.
Main Results:
- Significant SBH variations observed at atomic levels in defected heterojunctions.
- SBH approaching zero in areas with extended defects, indicating Ohmic contact.
- Effective SBH is intrinsically dependent on defect density and character.
Conclusions:
- The proposed method successfully explains experimental SBH variations and discrepancies in MoS2@metal systems.
- Demonstrated good agreement between calculated and experimental effective SBH values.
- Provides a pathway for understanding and manipulating SBHs in metal-semiconductor heterojunctions.
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