A sacrificial SU-8 mask for direct metallization on PDMS

A new fabrication technology utilizing SU-8 as a sacrificial mask for metallization of the PDMS surface is presented. The sacrificial SU-8 layer process offers superior performance for reliable and repeatable metallization on the PDMS layer. Sacrificial SU-8 masks from 45 mu m to 250 mu m thickness are successfully fabricated on the PDMS layer to pattern gold on the PDMS surface. These layers are successfully peeled off from the PDMS surface after a metal deposition step. Metal lines from 10 mu m to 500 mu m wide and 1 mm to 50 mm long are successfully patterned and tested. Furthermore, the sacrificial SU-8 mask can be removed within minutes to realize metal patterns on the PDMS surface and does not leave any residue after removal of the SU-8 layer. As this new process is intended for use in fabrication of microfluidic and biomedical microdevices, electrodes of an electro-enzymatic glucose sensor are presented to demonstrate the technology.