Fabrication of thermoformable circuits by laser patterning of metallized thermoplastic foils

Abstract

High-resolution laser patterning offers innovative methods for the manufacturing of three dimensional interconnect devices. The process chain presented in this paper uses cost efficient metal thin-films sputtered on thermoplastic sheets and two-dimensional high speed laser processing, whereas the three-dimensional shape of the end product is realized by deep drawing of the machined sheet. Due to the lower fracture strain of metals in comparison to thermoplastics extensive fragmentation of the deposited metal film occurs during deep drawing; therefore picosecond laser fine structuring is used to provide strain relief in the circuitry and to preserve the conductivity after the drawing process.