Low-Loss Non-Contact Interconnects Based on 3D Heterogeneous Redistribution Layer for Millimeter Wave Phased Arrays

This paper presents a study of the non-contact interconnection based on 3D heterogeneous redistribution layer (RDL), to improve the integration density and reduce system transmission loss of millimeter wave phased arrays for the 5G/6G communications. Low-loss non-contact interconnects between antenna and chip that consist of RF striplines, High-k dielectric and their transitions are designed. The simulated S-parameters show that the optimized design achieves insertion loss <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathrm{S}_{21}&gt;-3\text{dB}$</tex> and return loss <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathrm{S}_{11} &lt; -40\text{dB}$</tex>, within the band of 39.33 to 42.15 GHz. These results validate the possibility of heterogeneous RDL package for 5G mmW applications at mmW band.