Surface structuring and wettability control of Polyvinyl fluoride (PVF) using extreme ultraviolet (EUV) surface modification

Abstract

In this study, surface modification of fluoropolymer Polyvinyl fluoride (PVF) films was performed using Extreme Ultraviolet (EUV) radiations to induce patterned structures on surface and to provide control over the surface wettability. Specially developed laser produced plasma based EUV source was used for surface structuring. The double stream gas-puff target was produced by injection of krypton and xenon (KrXe) gas mixture into a hollow stream of helium. Commercially available EKSPLA Nd:YAG 1.06 micron laser was used to irradiate the KrXe gas puff target with 3 nanosecond pulse duration having 0.8 J energy. The PVF films were irradiated with 50 and 200 EUV pulses. The surface characterisation of the pristine and EUV modified PVF polymer films was performed by Atomic Force Microscopy (AFM) for morphological modifications. To investigate chemical modifications, X-ray Photoelectron Spectroscopy was used. The wettability of the sample surfaces was examined by Water Contact Angle (WCA) measurements. EUV surface modification of PVF films resulted in formation of wall type rippled structures on the polymer surfaces. The surface roughness of the EUV treated surfaces was increased up to 287 nm and 21° reduction was observed in the WCA of the PVF films. Successful surface structuring and wettability control was obtained using EUV surface modification of PVF films.