Hermetic-Equivalent Wafer-Scale Packaging of Radiation-Hardened Semiconductors for Use In Strategic Missile Guidance Systems

"Guidance systems used on sea-based vehicles are often stored forlong periods of time (10 to 30 years) under a variety ofuncontrolled storage and operational conditions. The electronicsare util-ized during the life of the system and must operate witha high degree of reliability when they are needed. The Navyanticipates a need for radiation-hardened ICs in packages thatwill ensure reli-ability and performance over long lifetimes.Ceramic-packaged hermetic circuits, currently used in themajority of missile systems, generally do not suffer from many ofthe common failure mecha-nisms, but they are quickly becomingobsolete as the military share of the overall electronics mar-ketcontinues to shrink. Current plastic-encapsulated die approacheshave not been proven reliable under long-term unpowered storagein harsh environments. To make plastic encapsulated die a viablealternative to ceramic packaged devices, an inexpensive yeteffective protection scheme must be developed to eliminate commonfailure mechanisms. This proposal entails application andqualification testing of a novel pre-encapsulated semiconductordie packaging approach that pro-vides superior ruggedness and issuitable for high-reliability defense environments. Notable ad-vances in materials and processes for wafer-scale pre-encapsulation and assembly have already been made, providing alow-risk path for implementation of prototypes.BENEFITS: The needs of missile guidance, space, and a