Alumina Passives Using the Interconnect Layer of Metal-Embedded Chip Assembly Processing

This paper describes the additional design dimension of a new heterogeneous packaging process, referred to as Metal-Embedded Chip Assembly (MECA). The interconnect layers of the process can be used as an additional degree of freedom for design and manufacturing of passive circuits for integrated RF front-ends. Transmission lines designed with the interconnect layer, referred to as bridge lines, with up to 35% higher characteristic impedances than their microstrip counterpart, are validated by measurements up to 25 GHz. An X-band Lange coupler with 3.9 GHz bandwidth is designed using MECA interconnects, with accurate bridge placement. Broadband measurements from 0 to 25 GHz show good agreement with simulations.