Fabrication of Self-standing Polystyrene Thin Films with Fine Through Holes by use of Water Soluble Resin Sacrificial Layer

Abstract

A simple fabrication process is developed for self-standing resin films with well-defined through-holes by use of imprint technology. Polyvinyl alcohol film, which can be dissolved in water, is used as a sacrificial film. A commercial bi-layer film sheet, where polyvinyl alcohol (PVA) film is laminated on polyethylene terephthalate (PET) film, is used. A mold pattern is directly transferred to the PVA film in the bi-layer film sheet, and polystyrene (PS) resin is coated on the patterned PVA film. The PVA sacrificial film is removed in water. A defect free PS self-standing film of 0.7 μm in thickness can be obtained in the fixing frame with 5 mm diameter hollow. Through-holes of 2.5 μm square are successfully fabricated in the PS self-standing film.