06190940 is referenced by 44 patents and cites 2 patents.

The specification describes techniques for soldering IC chips, or other components, to interconnection substrates using a patterned epoxy layer to define the solder interconnections. The epoxy layer is photodefined to form openings that expose the bonding sites on the IC chip (or alternatively the interconnect substrate). Solder paste is deposited in the openings. With the IC chip and the interconnect substrate aligned together, the solder paste is heated to reflow the solder and solder bond the IC chip to the substrate. Heating is continued to cure the epoxy, which serves the function of the conventional underfill. The shape of the solder interconnection is defined by the lithographically formed openings, and the interconnections can be made with very fine pitch. The application of the epoxy underfill in this manner assures complete filling of the gap between the IC chip and the interconnection substrate.

Title
Flip chip assembly of semiconductor IC chips
Application Number
9/235011
Publication Number
6190940 (B1)
Application Date
January 21, 1999
Publication Date
February 20, 2001
Inventor
Paul A Sullivan
Summit
NJ, US
Eric William Dittmann
Califon
NJ, US
Richard Alden DeFelice
Bernardsville
NJ, US
Agent
Thomas Kayden Horstemeyer & Risley
US
Agent
Peter V D Wilde
US
Assignee
Lucent Technologies
NJ, US
IPC
H01L 21/44
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