Browse Prior Art Database

CCGA Solder Segments Columns Fabrication

IP.com Disclosure Number: IPCOM000123237D
Original Publication Date: 1998-Jul-01
Included in the Prior Art Database: 2005-Apr-04
Document File: 2 page(s) / 52K

Publishing Venue

IBM

Related People

Caron, A: AUTHOR [+1]

Abstract

Using solder column connections in electronic component packaging is a new emerging technology, due to the possibility of high I/O connections. One of the problems encountered is the precision needed in the solder segments 10Sn/90Pb in order to use them for the cast (full reflow of the solder segments) and the wire process (no reflow of the solder preform). Both processes need tight tolerance due to product reliability and yield requirements.

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CCGA Solder Segments Columns Fabrication

   Using solder column connections in electronic component
packaging is a new emerging technology, due to the possibility of
high I/O connections.  One of the problems encountered is the
precision needed in the solder segments 10Sn/90Pb in order to use
them for the cast (full reflow of the solder segments) and the wire
process (no reflow of the solder preform).  Both processes need tight
tolerance due to product reliability and yield requirements.

   The following is a list of major problems encountered
using other processes and techniques, mostly caused by the material
softness of the solder wire:
  o  the cut ends bend due to the cutting blade action and due
     to accumulation of solder residue on the blade;
  o  Variation in length exceeding tolerance of .140 .002
     inches;
  o  Variation in diameter exceeding tolerance of .020 .001
     inches;
  o  Problems maintaining cylindrical shape needed to load the
     carrier fixtures with the columns.  They could not be loaded
     by the normal loading process using vibration and vacuum;
  o  Problems with the manufacturing process and yields due to
     the above.

   The new process starts by precutting 4 inch wire segments
from a spool of 1 pound of 10Sn/90Pb with a wire diameter of 0.61 MM.
The wire is partially straightened in order to form a straight piece.

   Several pieces are then introduced manually into a stack
of carriers (Fi...