We studied surface modification of a double layer protective coating (Al2O3/TiAlN) on steel induced by single fs laser pulse irradiation in ambient air. The pulses (λ = 775 nm, τ = 200 fs) were generated by a Ti:sapphire laser source. The pulse energy was varied from 0.32 μJ to 50 μJ, corresponding to an incident laser fluence of 0.11 J cm− 2 to 16.47 J cm− 2. The surface damage threshold was found to be 0.20 J cm− 2 and the alumina layer removal was initiated at 0.56 J cm− 2. This selective ablation of alumina was possible in a wide range of fluences, up to the maximum applied, without ablating the TiAlN layer beneath.
COBISS.SI-ID: 26019623
We have carried out a systematic study of the influence of Ne, Ar and Kr working gases on both plasma and film properties of RF magnetron sputtering of silver. We studied influence of magnetron power and working gas pressure on the plasma composition. Both mass and OES spectra revealed presence of highly excited plasma in the substrate vicinity for all sputtering gases. The increasing OES signal intensities of Ag and Ag+ with increasing RF power and gas pressure were observed. However, in Ar discharge there was no Ag+ signal detected by OES at lower pressures of 0.5 Pa and 1 Pa. Similar profiles of the energy distributions of the ions with a maximum located around 19 eV were obtained in Ar and Kr discharges at pressure of 3 Pa while a maximum at 28 eV was measured in Ne discharge. Silver thin film deposited in Ne gas revealed lower roughness than the films deposited in the other gases.
COBISS.SI-ID: 26421799