Inkjet Printing of SU-8; A Case Study for Microlenses

This paper describes a novel method to fabricate polymer MEMS based on the inkjet printing of SU-8, with a special emphasis on integrated micro-optical lens arrays. Inkjet control parameters are optimized in order to enable a stable and reproducible ejection of SU-8 drops in both continuous and drop-on-demand (DOD) modes. Arbitrary patterns of single and multiple polymer drops and arrays of convex microlenses are printed on different substrates. The influence of surface wetting properties on the size and the shape of the printed patterns is investigated. The optical properties of the microlenses are investigated in details. A model for inkjet printing of high-viscous functional materials for polymer MEMS has been used.