Structural and Optical Properties of ZrO₂ Thin Films Deposited by Reactive DC Unbalanced Magnetron Sputtering

Abstract:

Zirconium oxide (ZrO₂) thin films were deposited on Si-wafer and glass slide substrates by reactive DC unbalanced magnetron sputtering at different deposition times. A pure metallic zirconium target (99.97%) was sputtered in a gas mixture of argon and oxygen. The crystal structure was characterized by GI-XRD (grazing-incidence X-ray diffraction) whereas surface morphologies and films thickness were evaluated by AFM (atomic force microscopy). The transmittance spectrum was measured by spectrophotometer. The optical constants of the as-deposited films were calculated by Swanepoel method. It was found that the ZrO₂ films deposited on silicon substrates showed a highly monoclinic phase (-1 1 1). The as-deposited films showed high transmittance in visible range. The thickness and roughness varied from 155 nm to 502 nm and 3.1 nm to 3.6 nm, respectively, with increasing of deposition times. The optical constants namely refractive index (n) and extinction coefficient (k), at 550 nm, was about 1.9 - 2.1 and 0.0003 - 0.0009, respectively. In addition, the energy band gap (E_g) of the as-deposited film was approximately 4.17 eV.

• Periodical: Advanced Materials Research (Volume 979)
• Pages: 374-377
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.979.374
• Online since: June 2014
• Authors: Nirun Witit-Anun*, Surasing Chaiyakun
• Keywords: Optical Constant, Reactive DC Unbalanced Magnetron Sputtering, Thin Film, Zro₂

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