Self-Aligned Electrodes on SU-8 Negative Photoresist Pedestals

We report a novel technique by which self-aligned thin-film electrodes are fabricated on SU-8 negative photoresist pedestals. A bilayer aluminum and titanium structure is used to align the thin-film electrode and to serve as the optical mask for the UV exposure of the SU-8. The SU-8 developer is used to remove both the unexposed SU-8 and the bilayer structure of aluminum and titanium. The result is a thin-film electrode aligned on an SU-8 pedestal with a minimal undercut beneath the thin-film electrode.