Flexible, Reusable and Ultra-Thin Parylene-C/Cr Shadow Mask for Versatile Micropatterning Applications on Planar and Nonplanar Surfaces

In this paper, a reusable, flexible, and ultra-thin parylene-C/Cr shadow mask for fabricating diverse micropatterns on arbitrary surfaces is introduced. The shadow mask is composed of 3-μm parylene-C film and 100-nm Cr layer. The flexible nature of this ultra-thin shadow mask makes it easy to attach to any surfaces. The smallest feature size of the fabricated micropatterns can reach 3 μm and the shadow mask can be reused for more than six times with good integrity and high accuracy. Various etching and deposition micropatterns with different shapes and dimensions were successfully fabricated on both flat and curved surfaces with well-defined edges and good feature transfer fidelity. With the combination of this shadow mask and an atmospheric pressure microplasma jet, selective micropatterning can be easily achieved on conventional and unconventional substrates, especially the curved and bulky objects. The potential applications of this shadow mask technology cover multiple fields, including MEMS, flexible electronics, and biomedical applications.