Microstructure Formation on Poly (Methyl Methacrylate) Film Using Atmospheric Pressure Low-Temperature Plasma

This study targets development of a biomimetic technique for mitigating endoscope surface antifouling. We specifically examined a snail's shuck, which has convexo-concave microstructures, to achieve an antifouling function. Unfortunately, fabricating microstructures on lens surfaces entails large costs because of technical difficulties. As one alternative method, we fabricated microstructures on films with different PMMA concentrations and examined their surface profiles using atmospheric pressure low-temperature plasma. Convex structures on a low (67.4 wt%) PMMA concentration film have a rounded tip at high RF power. When RF power is low, however, structures fabricated on a 67.4 wt% PMMA film surface were more incisive and orderly than those on a 84.4 wt% PMMA film. Microstructures with 200-nm pitch, like a snail's shuck, were fabricated on a 67.4 wt% PMMA film when irradiating plasma at 52 W for 40 s.