Investigation of SiO2 thin films dielectric constant using ellipsometry technique

Sangpour, P; Khosravy, K; Kazemzad, M

Investigation of SiO2 thin films dielectric constant using ellipsometry technique

Authors

P Sangpour

K Khosravy

M Kazemzad

Abstract

In this paper, we studied the optical behavior of SiO2 thin films prepared via sol-gel route using spin coating deposition from tetraethylorthosilicate (TEOS) as precursor. Thin films were annealed at different temperatures (400-600oC). Absorption edge and band gap of thin layers were measured using UV-Vis spectrophotometery. Optical refractive index and dielectric constant were measured by ellipsometry technique. Based on our atomic force microscopic (AFM) and ellipsometry results, thin layers prepared through this method showed high surface area, and high porosity ranging between 4.9 and 16.9, low density 2 g/cm, and low dielectric constant. The dielectric constant and porosity of layers increased by increasing the temperature due to the changes in surface roughness and particle size.

Keywords

ellipsometry

sol - gel

dielectric constant

SiO2 thin film

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