Piezoelectric Stretchable Sensor with a Vertical Wavy Structure Fabricated by Combining Dip Coating and Micro-corrugation Process

Abstract

A novel fabrication process for a vertical wavy structured stretchable piezoelectric sensor combining dip coating and micro-corrugation process is proposed. By changing the dip coating withdrawal speed, the thickness of PVDF-TrFE (poly(vinylidene fluoride-trifluoroethylene)) films deposited on metal foils was controlled; the wave shape fabricated by the micro-corrugation process was influenced by the PVDF-TrFE film thickness. By reducing the PVDF-TrFE film thickness to less than 5 μm, the wave shape exhibited a high aspect ratio (wave height divided by wave pitch). From estimations obtained by measuring the change in substrate length before and after the microcorrugation process, the predicted stretchability is expected to be greater than 30%. The fabricated vertical wavy structured piezoelectric sensor with a PVDF-TrFE film thickness of approximately 2 μm showed more than 50% stretchability. The fabricated sensor was used as a finger-bending sensor for a virtual reality system, and the proposed process is a promising method for fabricating stretchable sensors.