First-principles calculations of strontium on Si(001)

TL;DR

This study uses first-principles calculations to analyze how strontium atoms deposit and form structures on silicon (001) surfaces, providing insights into surface reconstructions and phase stability relevant for heteroepitaxial growth.

Contribution

It presents a detailed phase diagram of strontium on Si(001), identifying stable reconstructions at various coverages and relating them to experimental data.

Findings

Identified surface reconstructions from 0 to 4/3 monolayers.

Proposed a phase diagram with stable phases at specific coverages.

Results aid understanding of heteroepitaxial growth of high-K oxides.

Abstract

This paper reports state-of-the-art electronic structure calculations on the deposition of strontium on the technologically relevant, (001) orientated silicon surface. We identified the surface reconstructions from zero to four thirds monolayers and relate them to experimentally reported data. A phase diagram is proposed. We predict phases at 1/6, 1/4, 1/2, 2/3 and 1 monolayers. Our results are expected to provide valuable information in order to understand heteroepitaxial growth of a prominent class of high-K oxides around SrTiO3. The insight obtained for strontium is expected to be transferable to other alkaline earth metals.