First-principles theoretical evaluation of crystalline zirconia and hafnia as gate oxides for Si microelectronics

TL;DR

This paper uses first-principles calculations to evaluate zirconia and hafnia as potential gate insulators in silicon electronics, focusing on their energetics, dielectric properties, and band alignment.

Contribution

It provides a comprehensive ab initio analysis of ZrO₂ and HfO₂, highlighting their favorable properties for use as gate oxides in silicon microelectronics.

Findings

Zirconia and hafnia have large dielectric constants.

They form stable, low-energy interfaces with silicon.

They exhibit large valence offsets and reasonable conduction barriers.

Abstract

Parameters determining the performance of the crystalline oxides zirconia (ZrO_2) and hafnia (HfO_2) as gate insulators in nanometric Si electronics are estimated via ab initio calculations of the energetics, dielectric properties, and band alignment of bulk and thin-film oxides on Si (001). With their large dielectric constants, stable and low-formation-energy interfaces, large valence offsets, and reasonable (though not optimal) conduction offsets (electron injection barriers), zirconia and hafnia appear to have a considerable potential as gate oxides for Si electronics.