Claims
- 1. A method of making a printed circuit board or card, comprising the steps of:
- a) forming a circuitized power core by depositing an electrically insulating material on a top side and a bottom side of a planar electrically conductive layer material;
- b) forming a plurality of holes through said circuitized power cores from said top to said bottom;
- c) plating electrically conductive material on the surface of the through holes and on the top and bottom surfaces of the electrically insulating layer of the circuitized power core adjacent each through hole, said material on the inside of said holes being continuous with the material on the top and bottom of the circuitized power core;
- d) placing within a ball dispenser assembly a plurality of substantially spherical balls having a diameter slightly larger than the diameter of said plated through holes in said circuitized power core and being made of electrically conductive material, said balls being arranged in a pattern matching the pattern of through holes formed in said circuitized power core;
- e) placing said circuitized power core over said planar surface on said ball dispenser assembly, aligning said plated through holes with holes in an exterior surface of said ball dispenser assembly, wherein said holes in said ball dispenser are slightly larger than said balls, and aligning location pins provided in said dispenser with location holes in said power core;
- f) placing a fixture base plate over said power core and securing said base plate to said ball dispenser;
- g) introducing pressurized gas into said ball dispenser causing said exterior surface to press against said power core and said power core to press against said base plate;
- h) inverting said ball dispenser, power core and base plate;
- i) vibrating the ball dispenser, power core and base plate, causing said balls to pass through said passages in said exterior surface and become wedged at the opening of said plated through holes;
- j) turning off said source of pressurized gas;
- k) heating the ball dispenser, power core and base plate to a temperature which melts only the material plated on the through holes;
- l) reverting the ball dispenser, power core, and base plate; and
- m) removing said base plate and said power core from said ball dispenser.
Parent Case Info
This is a divisional of Ser. No. 07/995,714 filed on Dec. 23, 1992.
US Referenced Citations (16)
Foreign Referenced Citations (5)
Number |
Date |
Country |
56-150897 |
Dec 1981 |
JPX |
3101191 |
Apr 1991 |
JPX |
4151895 |
May 1992 |
JPX |
5075253 |
Mar 1993 |
JPX |
6069640 |
Mar 1994 |
JPX |
Non-Patent Literature Citations (2)
Entry |
"Forming Electrical Interconnections Through Semiconductor Wafers" Anthony T. R., J. Applied Physics, Aug. 1981, pp. 5340-5349. |
IBM Technical Disclosure Bulletin, vol. 37, No. 2B, Feb. 1994, pp. 337-338. |
Divisions (1)
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Number |
Date |
Country |
Parent |
995714 |
Dec 1992 |
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