Performance Evaluation of Direct Write Thermoformed Additively Printed Silver Circuits With Electrically Conductive Adhesive for in Mold Electronics

Abstract The development of additively printed thermoformable circuitry for in-mold electronics (IME) has garnered immense interest due to its benefits, including flexible design, cost-effectiveness, weight reduction, and seamless integration into structural components. In this investigation, a direct-write printing technique is employed to print full-wave rectifier (FWR) circuits using stretchable conductive silver ink. The process involves utilizing a stretchable ink capable of thermoforming. Following the printing of conductive traces, surface mount devices (SMDs) are attached using electrically conductive adhesive (ECA). The effectiveness of the printed FWR circuit is assessed using an impedance analyzer. Thermoforming-compatible materials, such as High-Impact Polystyrene sheet and Polycarbonate substrates, are utilized. The dimensions of printed lines are measured through white-light interferometry, and the influence of process parameters on resistivity is examined. Parameters optimized from the printing and sintering analysis are applied to manufacture FWR circuitry. orcad software is employed to simulate the FWR circuit, and its performance is compared to the actual output of the printed thermoformed circuit. This investigation highlights the practicality of additively printed FWR circuits in IME using a direct-write process with thermoformable silver