Study of 3-D Printed Conical Inductors for Broadband RF Applications

This paper presents a study of the design, fabrication, and electromagnetic (EM) characterization of 3-D printed conical inductors for broadband radio frequency applications. A process flow for the design and fabrication of these components using stereolithographic 3-D printing in combination with electroless copper plating is proposed. A whole set of the samples corresponding to different geometrical parameters has been designed and fabricated using the proposed process flow. These parameters include the cone angle, the number of turns of the spiral, the metal width, and metal pitch. Experimental measurements and EM simulations have been carried out to determine the performance of conical inductors in terms of the equivalent inductance, the quality factor, and the frequency of the first resonance. The obtained results are discussed and correlated with the geometrical parameters of the samples and technological parameters of the fabrication process.