MMIC Coatings and Encapsulation for Non-Hermetic, Low Cost, Transmit/Receive Modules with the Reliability of Hermetic Packaging

The objective of this SBIR project is to develop a protective overcoat passivation process for wafer-level sealing of Monolithic Microwave/Millimeter wave IC (MMIC). The scarce supply of hermetic packaging choices and the high cost of mil-spec integrated circuit (IC) components used in military and aerospace applications have sparked research focused on using commercial off-the-shelf (COTS) packaging, such as plastic encapsulated microcircuit (PEM), while maintaining hermetic packaging reliability. Atomic layer deposition (ALD) grows continuous, pinhole-free and low-stress films with complete conformality to any surface topology. Such properties render ALD films ideal candidates for wafer-level protection of ICs. A low-cost alternative passivation process to the standard silicon oxide-silicon nitride process will be developed. Low temperature processing and thin films would be used to minimize impact on device reliability and RF performance. A thin film stack with hermetic-like performance would be developed during Phase I. Coated wafers will be die mounted and highly accelerated stress tested (HAST). During Phase I option a suitable ALD system for deposition of encapsulating wafers on MMICs will be designed. System integration and device-level validation will be performed at Phase II, as well as process integration and equipment refinement leading to commercial availability.