Nanoscale structures formed in silicon cleavage studied with large-scale electronic structure alculations; surface reconstruction, step and bending

TL;DR

This study uses large-scale electronic structure calculations to investigate silicon cleavage at the nanoscale, revealing surface reconstruction, step formation, and cleavage path bending consistent with experimental observations.

Contribution

It introduces a quantum mechanical approach to analyze silicon cleavage at the 10-nm scale, providing insights into surface stability and reconstruction mechanisms beyond traditional surface energy models.

Findings

Surface reconstruction and step formation during cleavage

Cleavage path bending into observed planes

Stability analysis of cleavage modes

Abstract

The 10-nm-scale structure in silicon cleavage is studied by the quantum mechanical calculations for large-scale electronic structure. The cleavage process on the order of 10 ps shows surface reconstruction and step formation. These processes are studied by analyzing electronic freedom and compared with STM experiments. The discussion presents the stability mechanism of the experimentally observed mode, the $(111)$-$(2 x 1)$ mode, beyond the traditional approach with surface energy. Moreover, in several results, the cleavage path is bent into the experimentally observed planes, owing to the relative stability among different cleavage modes. Finally, several common aspects between cleavage and other phenomena are discussed from the viewpoints of the nonequilibrium process and the 10-nm-scale structure.