An Oxygen‐Insensitive Degradable Resist for Fabricating Metallic Patterns on Highly Curved Surfaces by UV‐Nanoimprint Lithography

In this paper, an oxygen‐insensitive degradable resist for UV‐nanoimprint is designed, comprising a polycyclic degradable acrylate monomer, 2,10‐diacryloyloxymethyl‐1,4,9,12‐tetraoxaspiro [4.2.4.2] tetradecane (DAMTT), and a multifunctional thiol monomer pentaerythritol tetra(3‐mercaptopropionate) (PETMP). The resist can be quickly UV‐cured in the air atmosphere and achieve a high monomer conversion of over 98%, which greatly reduce the adhesion force between the resist and the soft mold. High conversion, in company with an adequate Young's modulus (about 1 GPa) and an extremely low shrinkage (1.34%), promises high nanoimprint resolution of sub‐50 nm. The cross‐linked resist is able to break into linear molecules in a hot acid solvent. As a result, metallic patterns are fabricated on highly curved surfaces via the lift off process without the assistance of a thermoplastic polymer layer.