Three Dimensional Micro Fabrication of Photoresist and Resin Materials by Using Gray-scale Lithography and Molding

Three dimensional structures on SU-8 photoresist were fabricated by gray-scale lithography. A thin glass substrate was plastered over with SU-8 and UV light was irradiated through the glass substrate. SU-8 structures with maximum 400 μm height and strong adhesion to the substrate were achieved by the lithography technique. The relation between gray-scale value and the resist height were evaluated and the maximum surface roughness of the structure was 0.98 μm. Three dimensional structures such as micro capillaries were fabricated on PDMS from the SU-8 structures by molding.