Наносекундное воздействие интенсивного лазерного излучения на тонкие плёнки TiAlN

The spectral dependencies (λ = 0.35-1.0 μm) of the transmittance and reflectivity (R) of TiAlN thin films deposited on glass and Si substrates by magnetron sputtering technique have been measured. The TiAlN/Si films of 0.5 μm thickness were irradiated by single nanosecond (70 ns) ruby laser pulses in order to study the influence of laser-induced thermophysical processes in TiAlN on its R(t) dynamics at the wavelengths λ1 = 0.53 and λ2 = 1.06 μm of probing radiation, and on the state of laser irradiation zones, which was studied by optical and scanning electron microscopy. The observed in the experiment and connected with the pulsed heating dynamics changes of R - increase at λ1 and decrease at λ2 amplifies as the irradiation energy density W approaches to the threshold of laser ablation of the nitride ~ 1 J/cm2. Laser-induced thermophysical processes, occurring at W = 0.6-0.9 J/cm2, lead to a specific modification of the TiAlN layer with the formation of a net of cracks due to thermal stresses arising during the laser pulse. The increase of W leads to the formation of a more developed net/cellular structure of the film with a smaller average size of cells.