Pulsed laser deposition grown diamond-like carbon coatings for wear protection

High power excimer laser driven PLD is employed for creating ultra-hard functional layers. Diamond-like tetrahedral amorphous carbon (ta-C) is grown on substrates that are moderately heated to below 90 °C in a vacuum chamber by ablation of a graphite target with a high pulse energy excimer laser at a wavelength of 248 nm. The rapid evaporation of the target material induced by the high photon energy of 5 eV, the short temporal width of 30 ns and the high fluence of the excimer laser pulses generates plume species with a high degree of ionization and high kinetic energies. As a result, the kinetic energies resulting from excimer-based PLD are significantly higher than those of thermal evaporation and ion sputter deposition methods. In fact, the average kinetic energy of atoms and ions in the plume is in the range of 30 eV to 80 eV at fluences of 5 J/cm² to 20 J/cm² .