The Features of Laser Microstructuring of PVDF Films with Nanosecond Pulses at 263 nm

This paper investigates laser microstructuring of ferroelectric polymer films based on polyvinylidene fluoride (PVDF) exposed to nanosecond UV radiation (λ = 263 nm). The selected irradiation parameters are found to ensure the formation of microgrooves and craters with minimal carbonization while maintaining the ferroelectric β phase, which was confirmed by Raman scattering (RS) spectroscopy. It is shown that the morphology of microstructures is sensitive to the focus position, and repeated laser irradiation improves their quality. Two characteristic energy density thresholds have been identified, corresponding to the transition from the material melting mode (Fth1 = 19 ± 12 J/cm2) to the thermal ablation mode (Fth2 = 50 ± 14 J/cm2). Fundamental differences in absorption mechanisms and ablation threshold modes have been established in comparison with similar results of treatment with femtosecond IR pulses (λ = 1032 nm). The study findings make the basis for developing functional micro- and nanoscale sensor elements and microelectronic devices based on PVDF.