Heteroepitaxial growth of high-K gate oxides on silicon: insights from first-principles calculations on Zr on Si(001)

TL;DR

This study uses first-principles calculations to investigate how zirconium deposits on silicon surfaces, revealing that Zr tends to form silicide islands and is thermodynamically unstable against silicide formation, impacting high-K oxide growth.

Contribution

It provides detailed atomic-level insights into Zr-silicon interactions, highlighting silicide formation tendencies relevant for high-K gate oxide development.

Findings

Zr forms silicide islands even at low coverage

Zr is thermodynamically unstable against ZrSi2 formation

Silicide grains are likely to form spontaneously

Abstract

Metal deposition of Zr an a Si(001) surface has been studied by state-of-the-art electronic structure calculations. The energy per Zr adatom as a function of the coverage shows, that Zr forms silicide islands even at low coverages. Adsorbed Zr is thermodynamically unstable against the formation of bulk silicide ZrSi2. The observation that the islands consist of structural elements of the bulk silicide is an indication that silicide grains will form spontaneously.