| Abstract
| - This paper demonstrates that the pattern of silver particlesembedded in the gelatin matrix of exposed and developedsilver halide-based photographic film can serve as atemplate in a broadly applicable method for the microfabrication of metallic microstructures. In this method, aCAD file is reproduced in the photographic film byexposure and developing. The resulting pattern of discontinuous silver grains is augmented and made electrically continuous by electroless deposition of silver, andthe electrically continuous structure is then used as thecathode for electrochemical deposition of an additionallayer of the same or different metal. The overall processcan be completed within 2 h, starting from a CAD file,and can generate electrically continuous structures withthe smallest dimension in the plane of the film of ∼30μm. Structures with aspect ratio of up to 5 can also beobtained by using the metallic structures as photomasksin photolithography using SU-8 photoresist on the top ofthe electroplated pattern and exposed from the bottom,followed by development and electroplating through thepatterned photoresist. This method of fabrication usesreadily available equipment and makes it possible todevelop prototypes of a wide variety of metallic structuresand devices. The resulting structureseither supportedon the film backing or freed from itare appropriate foruse as passive, structural materials such as wire framesor meshes and can also be used in microfluidic, microanalytical, and microelectromechanical systems.
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