Browse Prior Art Database

Soldering Fixture

IP.com Disclosure Number: IPCOM000050065D
Original Publication Date: 1982-Sep-01
Included in the Prior Art Database: 2005-Feb-09
Document File: 2 page(s) / 48K

Publishing Venue

IBM

Related People

Phelps, DW: AUTHOR [+3]

Abstract

In the joining of stacked chip carriers by soldering techniques, it is necessary to precisely align the stacked carriers so that the solder connections are properly aligned. The present fixture assures such proper alignment relying solely on gravity.

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Soldering Fixture

In the joining of stacked chip carriers by soldering techniques, it is necessary to precisely align the stacked carriers so that the solder connections are properly aligned. The present fixture assures such proper alignment relying solely on gravity.

Figs. 1 and 2 show a receiving fixture having an inclined base section 10 with a plurality of pins 12 projecting upwardly therefrom, Fig. 1 being a plan view and Fig. 2 a transverse sectional view. The pins are positioned to act as stops for a pair of superimposed upper and lower chip carriers 14 and 16. The lower chip carrier 16 has I/O pins 18 extending therefrom. Solder balls 20 are formed on one of the chip carriers and are positioned to align with connections on the other chip carrier to form a solder connection.

The fixture with the superimposed chip carriers thereon is placed in a furnace and heated to above the melting point of the solder. When the solder melts, the incline of the base 10 allows gravity to induce relative movement between the upper chip carrier 14 and lower chip carrier 16, thus allowing both to abut the pins 12 to precisely align the carriers for solder connection.

The angle Alpha of the base must be sufficiently great to allow gravity to act on the upper chip carrier, but not so great as to cause the melted solder to run. An angle of between 10 degrees and 20 degrees fulfills these requirements.

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