Structural, interfacial and optical characterization of ultrathin zirconia film grown by in situ thermal oxidation of sputtered metallic Zr films

G He; Q Fang; J X Zhang; L Q Zhu; M Liu; L D Zhang

doi:10.1088/0957-4484/16/9/040

Structural, interfacial and optical characterization of ultrathin zirconia film grown by in situ thermal oxidation of sputtered metallic Zr films

Nanotechnology. 2005 Sep 1;16(9). doi: 10.1088/0957-4484/16/9/040.

Authors

G He¹, Q Fang^{1

2}, J X Zhang¹, L Q Zhu¹, M Liu¹, L D Zhang¹

Affiliations

¹ Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, People's Republic of China.
² Electronic and electrical Engineering, University College London, Torrington Place, London WC1E 7JE, UK.

PMID: 34911205
DOI: 10.1088/0957-4484/16/9/040

Abstract

High dielectric constant ZrO₂gate dielectric thin films have been prepared by means ofin situthermal oxidation of sputtered metallic Zr films. XRD reveals that the as-oxidized samples are amorphous, but can be made polycrystalline with a highly ()-preferential orientation by increasing the annealing temperature. AFM measurements confirm that high temperature annealing results in increase of the roughness root mean square value of the films. The growth and properties of the interfacial SiO₂layer formed at the ZrO₂/Si interface are observed by using Fourier transform infrared spectroscopy. It has been found that the formation of the interfacial layer depends on the post-deposition annealing temperature. On the basis of a parametrized Tauc-Lorentz dispersion model, the optical properties of the as-oxidized and annealed films related to the annealing temperature are systematically investigated by spectroscopic ellipsometry. The increase in the refractive index and decrease in extinction coefficient with increase of the annealing temperature are discussed in detail.

Published under licence by IOP Publishing Ltd.