Fabrication of Well-Defined Mushroom-Shaped Structures for Biomimetic Dry Adhesive by Conventional Photolithography and Molding

Abstract

Biomimetic dry adhesives have many attractive features, such as reversible and repeatable adhesion against various surfaces. This paper presents a method for the simple fabrication of biomimetic dry adhesives composed of a mushroom-shaped structure, which is based on conventional photolithography and molding. Firstly a masked and a maskless exposure are performed on the top and bottom of a photoresist, respectively, that generates microholes with an undercut after development. This structured photoresist is then used for molding, leading to mushroom-shaped structural features after sacrificing the photoresist. Because of the convenience of photolithography, the proposed method has the potential to fabricate various dry adhesives cost-efficiently.