Diamond-like carbon films were prepared by pulsed laser deposition using 248 nm excimer laser wavelength and laser pulse energy fluences in the range of 6 to 30 J/cm². At those fluences the mean kinetic energies of the ablated species were in the range of 35 to 130 eV. Films prepared at substrate temperatures below 100°C are completely amorphous and have 80 to 85 % sp³ bonds (determined by EELS). As-deposited films show high compressive stresses in the range of 8 to 10 GPa. We investigated the possibilities to reduce those stresses by means of thermal annealing (as known from the literature [1]) and, in particular, by means of pulsed laser annealing. We will show that both methods allow the preparation of stress-free diamond-like carbon films with thicknesses of several micrometer and good adherence to Si, SiO₂, WC hard metal and Ge substrates. Critical loads up to 30 N (on Si) and 50 N (on WC) have been measured by means of scratch test. The optical and mechanical properties of those films have also been measured. Films have optical band gaps up to 2.5 eV and average surface roughnesses of 1.0 to 1.5 nm (on Si). Their Vickers microhardness was measured on 2 µm thick films on WC to be 85 to 95 GPa by using a dynamic indentation method. The Young´s modulus is about 800 GPa and the density some 3.3 g/cm³ (both determined by acoustical surface wave spectroscopy). In a final part some examples on laser microstructuring of those films using femtosecond laser pulses and on the preparation of free-standing membranes and ultrathin films will be shown.

[1] T.A. Friedmann, J.P. Sullivan, J.A. Knapp, D.R. Tallant, D.M. Follstaedt, D.L. Medlin, P.B. Mirkarimi, Appl. Phys. Lett. 71, 26 (1997) 3820.