  A multiscale studying integrating ab initio quantum mechanics, classical
molecular dynamics and two-temperature model, is carried out to study film
thickness dependent femtosecond laser spallation and ablation. As an interval
of 130.73 nm, five silver films with increasing thickness from 392.19 nm to
915.11 nm are simulated. Absorbed laser fluences of 0.1 J/cm^2 and 0.3 J/cm^2
are chosen to observe the laser spallation and ablation. The simulation results
show that film thickness has a close correlation with the Kelvin degree of
heating of the laser-irradiated silver films, which further affects femtosecond
laser spallation and ablation. Suggestions for precise micromachining are
proposed in this paper.
