RF characterization of a low cost multichip packaging technology for monolithic microwave and millimeter wave integrated circuits

This paper describes a unique multichip module technology based on highly impermeable liquid crystal polymers (LCPs) to interconnect and package Microwave and Millimeter Wave Monolithic Integrated Circuits (MIMICs). Because of the low moisture permeability of the LCPs, the packages can be made hermetic without heavy expensive housings, and can be two to four times lighter and one-fifth the cost of conventional ceramic based transmit/receive (T/R) modules. Preliminary results indicate that the LCP has a low dielectric constant, and low loss transmission lines can be manufactured on LCPs using large area processing techniques that provide a tremendous cost advantage over competing technologies. Using flip chip bonded MMICs attached to a high thermal conductivity, low coefficient of thermal expansion substrate, this innovative technology can meet a variety of commercial, military and space requirements.