Ellipsometric characteristics of diamond-like a-C:H films obtained by the r.f. PACVD method

The paper presents results of investigations on optical properties of different diamond-like a-C:H films obtained by using methane as monomer and the r.f. PACVD as deposition method on the medical steel AISI 316L measured by the spectroscopic ellipsometry technique. The investigated diamond-like films were produced using different process parameters: r.f. bias voltage, substrate temperature and methane flow. Measurements of the optical constants of all deposited films were carried out with the use of a special version of Jobin Yvonʹs spectral ellipsometer UVISEL, supplied with a double monochromator system, in the spectral range from 250 to 1700 nm. The refractive index n, the extinction coefficient k and the optical gap Eopt were calculated. The obtained results were verified by Raman spectroscopy executed using the micro-spectrometer T64000 produced by Jobin Yvon.