Conductive SU8-silver composite photopolymer

A new electrically conductive photosensitive composite resist has been formulated and used to build micro-components. This composite material is based on the SU-8 photopolymer, an insulating negative-tone photoresist, in which silver nano-particles have been dispersed to enhance the electrical properties of the polymer. The properties of this new photosensitive composite have been characterized by optical and electrical measurements. The patterned composite structures can be obtained for a wide range of values of the electrical conductivity, by varying the powder volume fraction of the composite. The lateral resolution of the produced structures were evaluated, and depending on the patterning conditions, can be better than 5 /spl mu/m.

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