Block Cooling and Block Power Supply for Semiconductor Chips With High Power Dissipation
Original Publication Date: 1985-Feb-01
Included in the Prior Art Database: 2005-Feb-18
A multitude of semiconductor chips 1 (Fig. 1) are back-bonded to a block 2 of thermally conductive material, preferably copper. The backs of chips 1 are metal-plated to allow an attachment technique affording good thermal conductance. The chips are wired by means of a multilayer plastic foil 3 wound around the block/chip assembly. The chips are C4-bonded to the foil. Connections to substrate 4 (Fig. 3) may be provided by any of the following: connector spring 5, ultrasonic bonding of the foil, the C4 process or an equivalent technique. The top of block 2 may be polished and pressed to a heat sink (not shown) or glued or soldered to it. A path with an even lower thermal resistance is obtained by providing block 2 with channels 6 which are traversed by a cooling medium 7, preferably water.