Soft lithography replication based on PDMS partial curing

Abstract

In this paper, a partial curing technique is presented. Its aim is to enable the soft lithography replication process for the case requiring usage of PDMS mold. Through controlling the curing time during molding step, the liquid PDMS prepolymer in original status, which will later constitute the device substrate, can be partially polymerized as well as solidified. As a result, not only can the structural pattern in the mold be successfully transferred into the device layer, but also the spontaneous adhesive interaction between these two PDMS parts happening during curing can be effectively limited within very low level, thus largely facilitating the demoulding process. Based on this process, several devices have been successfully developed and high fidelity pattern transfer capability has also been demonstrated. Comparing with the most commonly used treatments such as silanization, the presented method demonstrates easier operation and better user-friendly interface advantages.