Development of a highly transparent dry film resist system for UV-A/VIS exposure (λ=350-450 nm) and UV structuring with different layer gauges for the production of optical components

The R&D project is working on a negative photoresist material based on epoxy resin that is highly transparent, absorbs long wavelengths (above 400 nm), and can be processed with UV light. Dry films should offer excellent layer formation, homogeneous layers with minimal thickness tolerances, be easily laminated, allow high-resolution photolithography, and remain stable at room temperature. The dry film resists should be automatically applied, in a liquid state, to the carrier film, dried, and rolled up in layers with thicknesses ranging from 5 µm to 100 µm. The resulting dry films could be provided to interested clients for application to a range of substrates, free of defects, with standard lamination systems.

Another innovative goal pursued by the project concerns its investigation of how well the newly developed dry film resist could be photolithographically structured with high-power LEDs or with a direct writing laser for maskless lithography. The choice of the more sustainable, mercury-free and low-energy LEDs as light source or direct laser writing in the UV-Vis and UV-A range follows current developments at the makers of exposure systems and promises more environmentally friendly, cheaper, and faster structuring processes.

The project is co-funded by the European Regional Development Fund (ERDF).