journal article·2020-05-27Open access

Scattering Phenomena in Porous Sol-Gel-Derived Silica Films

Janusz Jaglarz, Piotr Dulian, Paweł Karasiński, Paweł Winkowski

Coatings· Volume 10· Issue 6

Abstract

This paper presents the results of investigations of optical scattering phenomena in porous silica films. SiO2 films were prepared by the sol-gel method and deposited on polished silicon wafers by the dip-coating technique. Fabricated films were studied using integrating sphere reflectometry, spectroscopic ellipsometry, atomic force microscopy, scanning electron microscopy, and angular resolve scattering. The spectral characteristics of the refractive and extinction indices and scattering extinction coefficients are presented. Additionally, the depolarization of reflected beam from samples was measured. The tested films were characterized by a thickness of 500 to 900 nm, a porosity of 50%, and refractive indices of less than 1.24. The observed depolarization of light reflected from SiO2 films resulted from surface and bulk scattering. This phenomenon resulted from the presence of surface and closed pores located in the bulk of SiO2 film.
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Research context

OpenAlex topics: Surface Roughness and Optical Measurements · Aerogels and thermal insulation · Optical Coatings and Gratings

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

Faculty of Materials Engineering, Cracow University of Technology, 31-155 Cracow, Poland

Faculty of Chemical Engineering and Technology, Cracow University of Technology, 31-155 Cracow, Poland

Department of Optoelectronics, Silesian University of Technology, 2, 44-100 Gliwice, Poland

Funding

Narodowym Centrum Nauki

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