A new approach to chip size package using meniscus soldering and FPC-bonding

A chip size package was developed using a tape carrier for interconnection and redistribution of the pads of high pincount integrated circuits (ICs). The complete package is 650 /spl mu/m thick including a 550 /spl mu/m thick chip and a 100 /spl mu/m thick flexible carrier. A three layer tape with g...

Full description

Saved in:
Bibliographic Details
Published in:IEEE transactions on components, packaging and manufacturing technology. Part C, Manufacturing packaging and manufacturing technology. Part C, Manufacturing, 1998-01, Vol.21 (1), p.51-56
Main Authors: Kallmayer, C., Jung, E., Kasulke, P., Azadeh, R., Azdasht, G., Zakel, E., Reichl, H.
Format: Article
Language:English
Subjects:
Copper
Costs
Gold
Integrated circuit interconnections
Integrated circuit packaging
Nickel
Production
Soldering
Surface finishing
Wafer bonding
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:A chip size package was developed using a tape carrier for interconnection and redistribution of the pads of high pincount integrated circuits (ICs). The complete package is 650 /spl mu/m thick including a 550 /spl mu/m thick chip and a 100 /spl mu/m thick flexible carrier. A three layer tape with gold or gold/nickel surface finish on the copper layer was used as flexible interposer. The production line which was established includes a low cost bumping on wafer level. The chips were provided with electroless Ni bumps on which a layer of eutectic Au-Sn solder was deposited by meniscus soldering. The bonding of these bumps to the flexible substrate was performed by fiber push connection (FPC) technology, a laser bonding method. Mechanical stability between the tape and the chip was achieved by application of a low stress adhesive prior to bonding. In a last step solder balls were placed on the tape and reflowed using a novel solder ball placement machine with an incorporated laser reflow unit. The package obtained is fully surface mount compatible, allowing easy processability.
ISSN:1083-4400
1558-1241
DOI:10.1109/3476.670028