Electronic structure and dielectric properties of dielectric gate material (ZrO2)x(SiO2)1−x

We have investigated the electronic structure and dielectric properties of (ZrO2)x(SiO2)1−x with x less than 0.5 using first-principles methods. Initial models of (ZrO2)x(SiO2)1−x were obtained by selecting random distributions of Zr and Si atoms on the cation sites of tetragonal ZrSiO4 according to...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Journal of applied physics 2004-06, Vol.95 (12), p.7918-7924
Hauptverfasser: Ouyang, Lizhi, Ching, W. Y.
Format: Artikel
Sprache:eng
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:We have investigated the electronic structure and dielectric properties of (ZrO2)x(SiO2)1−x with x less than 0.5 using first-principles methods. Initial models of (ZrO2)x(SiO2)1−x were obtained by selecting random distributions of Zr and Si atoms on the cation sites of tetragonal ZrSiO4 according to x. These models were relaxed using the Vienna ab initio simulation package with high accuracy. Subsequent electronic structure and dielectric properties analysis was performed using the ab initio orthogonalized linear combination of atomic orbitals method. Our results indicate that for x less than 1/8, the SiO2 matrix is not significantly changed and that there are no signs of defect states being introduced into the band gap. Meanwhile, the optical dielectric constant was significantly increased compared to pure SiO2. For x greater than 1/8, the optical dielectric constant enters a plateau region. Our results confirm the experimental findings that low-x Zr silicate can be a viable candidate for high-k dielectric materials.
ISSN:0021-8979
1089-7550
DOI:10.1063/1.1728291