Co-Design of High-Isolation Chip-Package-Board in eWLB Package for 77 GHz Automotive Radar Application

This paper presents a co-design of 76-81 GHz chip-package-board based on embedded wafer level ball grid array (eWLB) package. The layout features of chip, package, and board are necessary considered and modeled since many electromagnetic couplings among them exist, especially at high frequencies. By means of accurate electromagnetic modeling, some unanticipated couplings can be considered in EM model. The designed chip containing 3-transmit channels and 4-receive channels is based on TSMC 65-nm CMOS general-purpose technology and flip-chipped on printed-circuit board (PCB). Low insertion loss and wide impedance matching are realized by carefully designing redistribution layer (RDL) in eWLB package and the grounded coplanar waveguide (GCPW) line on PCB. In addition, by properly designing the loaded stubs of RDL, the isolation level between phased-array channels is obviously improved with almost no effects on transmission responses. The result paves the way for high isolation, and cost-effective systems for 77-GHz automotive radar application.