First-principles study on scanning tunneling microscopy images of hydrogen-terminated Si(110) surfaces

TL;DR

This study uses first-principles calculations to analyze scanning tunneling microscopy images of hydrogen-terminated Si(110) surfaces, revealing the electronic origins of differences between filled- and empty-state images.

Contribution

It provides a detailed theoretical explanation for STM image features of Si(110) surfaces, linking local density of states to observed imaging differences.

Findings

Filled-state images match experimental results

Empty-state images differ significantly from filled-state images

Bonding and antibonding states influence image contrast

Abstract

Scanning tunneling microscopy images of hydrogen-terminated Si(110) surfaces are studied using first-principles calculations. Our results show that the calculated filled-state images and local density of states are consistent with recent experimental results, and the empty-state images appear significantly different from the filled-state ones. To elucidate the origin of this difference, we examined in detail the local density of states, which affects the images, and found that the bonding and antibonding states of surface silicon atoms largely affect the difference between the filled- and empty-state images.