Silicon-mold-based fabrication method for manufacturing polyimide membrane with nano-protuberance array structure

A fabrication method based on the silicon mold for manufacturing antireflection PI membrane with nano-protuberance array structure is proposed. In this method, a silicon mold with nano-hole array is firstly fabricated by using PS sphere self-assembly, metal coating and reactive ion etching. Then, the PI precursor solution is spin coated on the silicon mould. Followed by the imidization with gradient increased temperature, the PI membrane with nano-protuberance array structure is obtained. Tested by SEM and AFM, the proposed method possesses a high replication accuracy. The fabricated mold and membrane show large-area ordered and good uniformity. The reflection testing result shows that the proposed method can be used to decrease the reflection of PI membrane efficiently.