Researchers have pioneered a breakthrough method to rapidly 3D print fully functional electronic circuits. The circuits, which contain electrically-conductive metallic inks and insulating polymeric inks, can now be produced in a single inkjet printing process where a UV light rapidly solidifies the inks.
The breakthrough has established an underpinning technology that has potential for growth in academia and industry. The project has led to several collaborations to develop medical devices, as well as other applications. The breakthrough technique paves the way for the electronics manufacturing industry to produce fully functional components such as 3D antennae and fully printed sensors from multiple materials including metals and plastics.
The new method combines 2D printed electronics with additive manufacturing (AM) or 3D printing — which is based on layer-by-layer deposition of materials to create 3D products. This expands the impact of multifunctional additive manufacturing (MFAM), which involves printing multiple materials in a single additive manufacturing system to create components that have broader functionalities.
The new method overcomes some of the challenges in manufacturing fully functional devices that contain plastic and metal components in complex structures, where different methods are required to solidify each material.
The breakthrough speeds up the solidification process of the conductive inks to less than a minute per layer. The team found that silver nanoparticles in conductive inks are capable of absorbing UV light efficiently. The absorbed UV energy is converted into heat, which evaporates the solvents of the conductive ink and fuses the silver nanoparticles. This process affects only the conductive ink and thus, does not damage any adjacent printed polymers.