A Broadband D-Band Cavity-Backed Coupled-Feed Patch Antenna in Wafer Level Package

Abstract

A broadband D-band cavity-backed coupled-feed patch antenna in wafer level package is proposed. Benefiting from the thicker dielectric substrate and the coupled feed method, the patch antenna can achieve a broadband performance with a relative bandwidth of 25.8%. The influence of surface wave caused by the thicker dielectric substrate on the radiation performance of antenna can be partially reduced using metal backed cavity. Therefore, the antenna can obtain a high gain around 7 dBi with low sidelobe. For the D-band long distance high-speed communications, the 2×4 array is formed by the proposed antenna to obtain the higher gain of around 12.7 dBi. In addition, the designed antenna can adopt wafer-level package on Benzocyclobutene (BCB) process, and the BCB material is used as the substrate and interconnection layer to achieve low-loss interconnection with the RF chip through transmission line and vias.