Production and Validation of Non-Planar Electroplated 3D Printed Circuit Boards

Abstract Multi-material 3D Printing is an emerging technology that allows users to create more complex and more functional products using multiple filament options. Many methods and systems are currently used to accomplish a multi-material print and the machines capable of this process have improved significantly in recent years. Electroplating is a process that allows for thin layers of metal to be deposited onto conductive substrates. It is achieved through an electrical-chemical reaction where an anode of a sacrificial material is charged alongside a cathode of the desired object to be plated while they are both submerged in an electrolytic solution. Passing a current through the solution for an extended period of time allows for ions of the sacrificial anode to attach to the cathode and form a uniform layer. Combining these two manufacturing processes allows for the creation of non-planar, electrically conductive traces, or Printed Circuit Boards (PCBs). For this work samples were printed on a Lulzbot Pro Dual Extruder model with a traditional Polylactic Acid (PLA) filament and an electrically conductive PLA filament in an orientation that allowed smooth, continuous traces to be manufactured. The specimens were then submerged as the cathode in a copper-sulfate electroplating solution alongside a specified amount of copper proportionate to the surface area that was coated for a set duration to produce a copper layer on the traces. A frequency response analysis (FRA) was performed with the electroplated sample. Using this FRA data, the resonant frequency was quantified to show where and how strongly the frequency-based impedance affects the circuit’s performance. In conjunction with FRA, a Wheatstone Bridge was constructed in accordance with IEEE Std118-1978 to measure the resistance of the trace to characterize the resistivity of the material. These values were compared with results from standard copper. using statistical methods.