Lithographic micropatterning on the β‐PVDF film using reactive ion etching aim for high‐resolution skin sensors.

We report a method for high‐fidelity lithographic patterning of the flexible β‐phase polyvinylidene difluoride (PVDF) film using traditional cleanroom equipment and commercially available materials. In our process, the chemically reactive gas of CHF3, CF4 and SF6 was used as a simple substance mixed with O2. The effects of process parameters on the PVDF dry etching characteristics were investigated by controlling that of Radio frequency (RF) power, process pressure, gas type and the mixed concentration in O2 as well as its mass flow rate. At a constant RF power (100 W) and associated process conditions, 40–70 µm of fine‐line patterns and several tens µm/h of high etch rate could be realized on a 110 µm‐thick β‐PVDF film without much loss of its piezoelectricity. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]