First-Principles Study on Leakage Current through Si/SiO$_2$ Interface

TL;DR

This study uses first-principles calculations to analyze how defects at the Si/SiO2 interface, especially dangling bonds, significantly increase leakage current, affecting dielectric reliability and suggesting hydrogen termination as a mitigation strategy.

Contribution

It provides a detailed theoretical analysis of defect-induced leakage currents at the Si/SiO2 interface, highlighting the impact of dangling bonds and hydrogen termination.

Findings

Dangling bonds increase leakage current by 530 times.

Orientation of dangling bonds affects insulating performance.

Hydrogen termination reduces leakage current.

Abstract

The relationship between the presence of defects at the stacking structure of the Si/SiO$_2$ interface and leakage current is theoretically studied by first-principles calculation. I found that the leakage current through the interface with dangling bonds is 530 times larger than that without any defects, which is expected to lead to dielectric breakdown. The direction of the dangling bonds is closely related to the performance of the oxide as an insulator. In addition, it is proved that the termination of the dangling bonds by hydrogen atoms is effective for reducing the leakage current.