Fabrication methods and structures for micro-reservoir devices

Abstract

Methods are provided for making a multi-reservoir device comprising (i) patterning one or more photoresist layers on a substrate; (ii) depositing onto the substrate at least one metal layer by a sputtering process to form a plurality of reservoir caps and conductive traces; (iii) removing the photoresist layers using a liftoff process; (iv) forming a plurality of reservoirs in the substrate; (v) loading each reservoir with reservoir contents (such as a drug or sensor); and (vi) sealing each reservoir. Optionally, the reservoir cap comprises a first conductive metal layer coated with one or more protective noble metal films. To enhance the resistance of the substrate (e.g., a silicon substrate) to etching in vivo, the interior sidewalls of the reservoirs optionally can include a protective coating (e.g., gold, platinum, carbon, silicon carbide, silicon dioxide, and platinum silicide), or sidewalls comprising silicon can be doped with boron or another impurity.