Abstract: The problem of stress transmission from the outside of an integrated circuit package into the interior of the semiconductor has been significantly reduced by placing a micro-spring between the external solder ball and the interior tab. The process for manufacturing such a structure begins with a fully completed integrated circuit on whose surface freestanding metal posts are formed, each post being in contact with an I/O pad. Using a leveling plate at elevated temperature, the posts are given a permanent tilt relative to the surface and are then encapsulated in an elastomer. This subprocess may then be repeated as many times as desired with the direction in which the posts lean being changed by 90 degrees at each iteration. This results in the formation of an orthogonal spiral which acts as a coil spring to absorb stress originating at the solder ball.

Abstract: A multiple integrated circuit chip structure provides interchip communication between integrated circuit chips of the structure with no ESD protection circuits and no input/output circuitry. The interchip communication is between internal circuits of the integrated circuit chips. The multiple integrated circuit chip structure has an interchip interface circuit to selectively connect internal circuits of the integrated circuits to test interface circuits having ESD protection circuits and input/output circuitry designed to communicate with external test systems during test and burn-in procedures. The multiple interconnected integrated circuit chip structure has a first integrated circuit chip mounted a second integrated circuit chip to physically and electrically connect the first integrated circuit chip to the second integrated circuit chip.