The aim was the uniform fabrication of high aspect ratio polymer-based MOEMS (microoptical-electrical-mechanical system) on small and/or fragile samples, such as GaAs. The printing conditions were optimized, and the resulting thickness uniformity profiles were compared to those obtained via lamination and SU-8 standard spin-coating. Under the best conditions tested, STP and lamination produced similar results, with a maximum deviation to the central thickness of 3% along the sample surface, compared to greater than 40% for SU-8 spin-coating. Both methods were successfully applied to the collective fabrication of DF1050-based MOEMS designed for the dynamic focusing of VCSELs (vertical-cavity surface-emitting lasers). Similar, efficient electro-thermo-mechanical behaviour was obtained in both cases.

This study aims at focusing a laser beam at the center of a microfluidic channel for optical bio-sensing applications thanks to the collective integration of tunable microlens arrays on VCSELs devices. High aspect-ratio polymer-based MOEMS are successfully fabricated on small-sized samples using thick dry photoresist films. Such dry films are easier to use and less expensive than standard thick SU-8 and can be efficiently stacked on fragile GaAs samples using a soft-thermal-printing technique. By combining double UV exposure and planar metallization, uniform fabrication of MOEMS arrays is enabled and fabricated devices exhibit reproducible electro-thermal behavior.