Carbon Fiber-Based Grid Array Interconnects

This paper presents a new type of grid array electrical interconnect that uses carbon fiber as the conductive medium. Characterization of the electrical properties suggest that carbon fiber-based interconnects can be applied across different packaging levels, such as semiconductor die to substrate, integrated circuit package-to-board and board-to-board interconnections. Multiple interconnect contacts have been integrated to provide multiple interconnections within a single assembly. Each interconnect contact consists of a large number of carbon fibers which can act cooperatively to provide a high degree of reliability and predictability to the interconnect function. An optional metal coating, such as nickel, copper, aluminum or gold, can be applied over the carbon fibers to enhance conductivity and solderability. These novel interconnects can be joined to conventional circuitry by several techniques including pressure/physical contact, solder, and conductive adhesives (U.S. Patent 007 220 131).