A high-density electronic module (24) is disclosed, which is suitable for use as a DRAM, SRAM, ROM, logic unit, arithmetic unit, etc. It is formed by stacking integrated-circuit chips (22), each of which carries integrated circuitry. The chips are glued together, with their leads along one edge, so that all the leads of the stack are exposed on an access plane (28). Where heat extraction augmentation is needed, additional interleaved layers are included in the stacks which have high thermal conductivity, and are electrical insulators. These interleaved layers may carry rerouting electrical conductors. Bonding bumps (31 and 34) are formed at appropriate points on the access plane. A supporting substrate (26), formed of light transparent material, such as silicon, is provided with suitable circuitry and bonding bumps (38 and 42) on its face. A layer of insulation is applied to either the access plane or substrate face, preferably the latter. The bonding bumps on the insulation-carrying surface are formed after the insulation has been applied. The substrate face is placed on the access plane of the stack, their bonding bumps are microscopically aligned, and then bonded together under heat and/or pressure. A layer of thermally conductive (but electrically non-conductive) adhesive material is inserted between the substrate and stack. The substrate and stack combination is then placed and wire bonded in a protective container having leads extending therethrough for external connection.

High-density electronic modules, process and product
Application Number
Publication Number
Application Date
October 20, 1987
Publication Date
May 5, 1989
Go Tiong C
Irvine Sensors Corporation
H05K 07/02
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