Microwave multi-chip module utilizing aluminum silicon carbide with in-situ cast components and high density interconnect technology

Multi-Chip Module (MCM) designs of today place ever increasing demands upon packaging technologies. With increasing functionality and power levels being compressed into smaller packages, the packaging density and thermal performance of the module substrate has to keep pace. Further the unit cost of these substrates has increased along with performance demands. The packaging approach discussed in this paper eliminates traditional substrates entirely by leveraging the multi-layer routing capability of Lockheed Martin High Density Interconnect (HDI) Technology. Bare die are inserted directly, into a CTE-matched Aluminum Silicon Carbide (Al/SiC) housing with in-situ cast feedthrus and seal ring. Die interconnect and routing are completed entirely in the HDI overlay. This paper describes a high power microwave module designed and fabricated using Al/SiC-based HDI technology. Design and fabrication issues for this packaging technology are presented and comparisons to other packaging technologies are discussed.