Abstract: There is provided an edge connectable electronic package. The package has a metallic base at least partially coated with a dielectric layer. An interconnection means taking the form of either a leadframe or a circuit trace is electrically interconnected to an encased semiconductor device. The opposing end of the interconnection means extends to the package perimeter for interconnection to a socket or brazing to external leads.

Abstract: The bending of a ball grid array electronic package having a metallic base is reduced minimizing stresses applied to the innermost row of solder balls when the package base is cyclically heated and cooled. Reducing the stresses applied to the solder balls increases the number of thermal cycles before solder ball fracture causes device failure. Among the means disclosed to reduce the bending moment are a bimetallic composite base, an integral stiffener, a centrally disposed cover bonded to an external structure and a package base with a stress accommodating depressed portion.