Dynamic optical response of SU-8 upon UV treatment
Date of Original Version
We report the optical properties of SU-8 in the mid-infrared (mid-IR) region before and after UV treatment. Samples consisted of SU-8 films of thickness ranging from 10 um to 157 um deposited on gold coated silicon substrates and were prepared using spin coating. Mid-IR diffuse reflectance measurements were conducted using Fourier transform infrared spectroscopy. Spectra measurements imply a change in optical properties of SU-8 upon exposure to UV and heat treatment. A gradual change in optical properties is seen after each step of UV treatment and the baking process. Reflectance spectra of thin-films were also observed to be thickness dependent. We calculate the dielectric function of SU-8 in the range 2 um to 15 um using the reflectance spectra of the samples.
Optical Materials Express
Ghanekar, Alok, Matthew Ricci, Yanpei Tian, Otto Gregory, and Yi Zheng. "Dynamic optical response of SU-8 upon UV treatment." Optical Materials Express 8, 7 (2018): 2017-2025. doi:10.1364/OME.8.002017.