Low-Loss Graded Dielectrics via Active Mixing of Nanocomposite Inks During 3D Printing
Additive manufacturing has emerged as a promising approach for fabricatinggraded refractive index structures that control the electromagneticresponse of radio frequency (RF) devices. However, current 3D printingmethods cannot produce continuous gradients from multiple materials.Here, low-loss graded dielectrics via active mixing of nanocomposite inkscomposed of block copolymers and oxide nanoparticles are designed andprinted. By simultaneously tailoring their rheological, printing, and their localfiller particle-to-polymerratio using an active mixing printhead, a conductivemicrostrip-graded substrate matching network with a gradually changingdielectric response, is created. In these printed devices, the impedance of theRF signal is controlled by the graded substrate rather than by varying the conductivemicrostrip geometry, enabling the fabrication of smaller RF devices.This approach enables the rapid design and fabrication of high-performanceRF devices with locally tunable dielectric properties.
