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Integrated Circuit Component

IP.com Disclosure Number: IPCOM000091160D
Original Publication Date: 1969-Nov-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 2 page(s) / 48K

Publishing Venue

IBM

Related People

Arnold, WR: AUTHOR [+2]

Abstract

This method is for fabricating an integrated circuit module with improved heat dissipation characteristics. In step A, molybdenum cooling plate 1 is brazed to copper stud 2. This composite structure is then nickel- and gold-plated to a thickness of 100-150 microinches. Then, in step B, circuit chip 3 is bonded to the upper surface of plate 1. The latter, in conjunction with stud 2, provides a greater surface area for dissipation of heat generated by circuit chip 3. In step C, lead frame 4 is then joined to chip 3. The upper surface of chip 3 has along its outer perimeter solder pads 5 which provide electrical connections to the integrated circuits in chip 3. Frame 4 is positioned over plate 1 with the leads being in registry with pads 5.

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Integrated Circuit Component

This method is for fabricating an integrated circuit module with improved heat dissipation characteristics. In step A, molybdenum cooling plate 1 is brazed to copper stud 2. This composite structure is then nickel- and gold-plated to a thickness of 100-150 microinches. Then, in step B, circuit chip 3 is bonded to the upper surface of plate 1. The latter, in conjunction with stud 2, provides a greater surface area for dissipation of heat generated by circuit chip 3. In step C, lead frame 4 is then joined to chip 3.

The upper surface of chip 3 has along its outer perimeter solder pads 5 which provide electrical connections to the integrated circuits in chip 3. Frame 4 is positioned over plate 1 with the leads being in registry with pads 5.

The entire structure is then placed in a heating environment sufficient to cause the solder to reflow so as to achieve a soldered connection between the leads and pads 5. In step D, leads 6 of frame 4 are welded to plate 1 so as to provide a ground lead to frame 4. After welding, the encapsulation process step in step E is performed. This consists of applying a small amount of epoxy resin 7 to the chip area and then placing the entire structure in an oven at approximately 80 degrees C until the resin is cured. Frame 4 is trimmed at the corners to allow bending. In step F, leads 9 are then bent upward by pressing the structure in a bending tool. The unit is placed in mold 10 and further epoxy resin mat...