Modeling and Additive Manufacturing of Inductors in Complex Geometries for High Temperature Electronics

High-temperature electronic circuits are becoming increasingly important in a variety of commercial applications, particularly in extreme high-temperature environments. These circuits are instrumental in applications including on-engine sensors, which must withstand elevated temperatures, such as 150°C for general applications and up to more than 500°C for aircraft engines. Many of these high-temperature electronic circuits and sensors rely on inductors, which are fundamental components for creating filters, oscillators, transformers, and bias chokes. Additive manufacturing or direct write, a cost-effective and efficient production method, has been used to create 2D inductors with intricate designs and integrated components. These 2D printed inductors closely resemble their traditionally manufactured counterparts but offer cost and time advantages. However, 2D inductors face limitations when it comes to increasing their inductance values especially with direct write materials and fabrication methods. To achieve higher inductance, they require more space, often in the form of increased turns within the flat plane. The integration of a core material inside these turns in a 2D inductor is not feasible, and this area has remained unexplored in the literature. This paper introduces a new solution by presenting a conical 3D version of an additively designed high-temperature inductor up to 750°C. This approach incorporates a 3D printed ceramic substrate and aerosol jet printed high-resolution gold inductor conductor. Our approach encompasses parametric design and simulation study addressing the effect of the number of conductors turns, spacing, and core materials type and volume. Results highlight that the integration of ferromagnetic materials, resulted in a remarkable enhancement in the inductance and Q-value of the inductor. Compared to its 2D counterpart, this 3D design achieves a twofold improvement in performance while reducing the footprint by more than half.