Spectroscopic ellipsometry investigations of porous SiO2 films prepared by glancing angle deposition

• Published in: Surface and interface analysis Vol. 45; no. 11-12; pp. 1690 - 1694
• Main Authors: Yang, Shenghong, Zhang, Yueli
• Format: Journal Article
• Language: English
• Published: Chichester Blackwell Publishing Ltd 01.11.2013; Wiley; Wiley Subscription Services, Inc
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; glancing angle deposition; Physics; porous SiO2 films; pseudorefractive index; spectroscopic ellipsometry; porous SiO; films; Inorganic compounds; spectroscopic ellipsometry; glancing angle deposition; Silicon oxides; pseudorefractive index; Porous materials; Ellipsometry
• DOI: 10.1002/sia.5308
• ISSN: 0142-2421

We present the optical and the structural properties of porous SiO2 films fabricated by using a glancing angle deposition technique. The influence of the glancing angle on the pseudorefractive index of porous SiO2 films was studied by spectroscopic ellipsometry in the UV–visible region. The relationships among the pseudorefractive index, the porosity, and the glancing angle are determined. The results show that the pseudorefractive index decreases and the porosity increases with the increase of glancing angle. The minimum pseudorefractive index is found to be 1.11 at 532 nm for the porous SiO2 film deposited at a glancing angle of 87°. The structural and surface morphology of these samples was also investigated by using a scanning electron microscope. The results indicate that the as‐deposited SiO2 thin films are porous with a tilted‐columnar structure and low pseudorefractive index. Copyright © 2013 John Wiley & Sons, Ltd.