Transfer imprint lithography using a soft mold

In order to simplify the nanoimprint process and allow thick metal sacrificial layer deposition for high-aspect-ratio etching, a transfer imprint lithography technique is introduced. A metal layer is deposited on PDMS mold, and it is subsequently imprinted against an uncured nanoimprint resist layer spin coated on the substrate. The curing of nanoimprint resist by UV exposure naturally provides adhesion between the metal and substrate. The use of soft PDMS mold generates conformal contact of patterns with target surfaces and greatly reduces the imprinting pressure required for homogenous mask transfer.