Strain gauge circuit to be embedded in fiberglass

strain-gaugeSituation: Miniature electronic circuits to be embedded in fiberglass were needed by an airframe research group.

Problem

Techniques were required for building miniature electronic circuits that could be embedded in a fiberglass structure. Miniaturization was needed to avoid mechanical perturbation of the structure, and a single layer design was desirable.

Solution
Single-layer high-density electronic interconnect structures were developed that were based on filling of laser-milled channels with nanoparticle silver material. Fifteen-micron conductor widths allowed employment of novel routing techniques to achieve a single-layer design. In a proof of principle demonstration, a functional strain gauge interface circuit with 5 IC’s and 30 passive components was fabricated in an area of approximately 1 sq in. With an overall height of 1 mm, the circuit was suitable for embedding in a fiberglass layup.