An approach to achieve co-axial picosecond laser pulsed pair is proposed. Instead of introducing additional optical devices, this method involves the adjustment of switching-out dynamics in the regenerative amplification process. Experimental results concerning the dependence of laser output behavior on the duration of the quarter-wave voltage applied on the Pockels cell are reported. The influence of ablation mode (single pulse or double pulse) on the morphology of deposited Nickel-films is studied. A significant improvement in the surface morphology with the double pulse mode is observed. Fewer nanoparticles are observed and the thin film appears to be smoother with lower roughness.

An approach to achieve uniform and smooth molybdenum (Mo) film on a BK7 glass plate at room temperature is proposed through picosecond pulsed laser deposition, with the pulsed laser radiating the target along a linear track. A numerical model is established to analyze the influence of linear scanning offsets on the thickness homogeneity of the deposited thin film. Through an appropriate choice of radiation intensity and scanning parameters, a uniform and smooth layer of Mo thin film is prepared with its maximum thickness variation and root-mean-square roughness better than 5% and 1.2 nm, respectively.

We studied the influences of the number of sub-pulses within a burst on the surface morphology of Al thin films deposited by picosecond pulsed laser. It can be demonstrated that with an increasing number of sub-pulses within a burst, both the thin film morphology and the surface roughness are gradually improved. Several physical mechanisms are proposed to explain the reduction in the size of particulates inside and on the film surface. The burst mode not only alleviates the inherent particulates generation of ultra-short pulsed laser deposition also provides a higher degree of freedom in the tunability of the film surface.