Investigation of the optical properties of organic-inorganic hybrid polymers by IR to Vis-fUV spectroscopic ellipsometry

Inorganic-organic hybrid polymers are used as barrier coatings in order to protect flexible electronic devices from the permeation of atmospheric oxygen and water vapour that induce oxidation to the Flexible Electronic Device (FED) organic layers, reducing their operation, efficiency and stability. In this work, Spectroscopic Ellipsometry (SE) in a wide spectral region, from the infrared (IR) (900-4000 cm-1) to the Vis-far UV (1.5-6.5 eV) has been implemented in order to investigate the optical properties of different types of hybrid polymers, which are synthesized via the sol-gel technique onto Polyethylene Terephthalate (PET), SiOx/PET and AlOx/PET substrates. The analysis of the measured SE spectra revealed valuable information about the electronic and vibrational response as well as the cross-linking mechanisms that control the interface and barrier properties of these materials. Finally, the correlation of the optical properties with the synthesis parameters and th e barrier response of these materials will significantly contribute towards their optimization in order to be used as high barrier coatings.