Plasma 2D modeling and diagnostics of DLC deposition on PET

摘要

The possibility to apply two dimensional (2D) emission spectra of short-lived excited species for estimating the uniformity of production of ions and radicals that have an important role in the deposition of diamond-like coatings on polymeric substrates was investigated. Images of the alpha-balmer line of atomic hydrogen in CH_4/H_2 discharges were recorded under various total gas pressures and substrate bias voltages to reveal that the increase of the total gas pressure enhances radial non-uniformities of the electron population with energy higher than 16 eV. A comparison between these images and the results of a 2D simulator of CH_4/H_2 discharges shows that the most abundant ions (H_3~+, CH_5~+) and radicals with high reactivity in the gas phase (CH_2, CH, C) present similar axial and radial distribution with these emission maps.