05133495 is referenced by 115 patents and cites 21 patents.

A method of bonding a flexible circuitized substrate to a circuitized substrate (e.g., printed circuit board) to interconnect selected circuitry of both substrates using solder. Solder paste is applied over conductive pads on the circuitized substrate and organic dewetting material (e.g., epoxy coating) adjacent thereto. The flexible substrate, having conductors located within and/or traversing an aperture in the flexible substrate's dielectric, is positioned above the solder paste and heat is applied (e.g., in an oven). The paste, dewetting from the organic material, forms a substantially spherical ball and connects to the flexible circuit's conductor, connecting the two. In an alternative embodiment, the solder ball is formed to its desired shape and cooled (to solidification), separate from the flexible circuitized substrate. The flexible substrate is then lowered until the conductor engages the solder ball's upper surface. Heat is then applied to bond solder and conductor.

Title
Method of bonding flexible circuit to circuitized substrate to provide electrical connection therebetween
Application Number
7/745139
Publication Number
5133495
Application Date
August 12, 1991
Publication Date
July 28, 1992
Inventor
Orr Randy L
Vestal
NY, US
Thomas E Kindl
Endwell
NY, US
Patrick T Flynn
Owego
NY, US
Christopher G Angulas
Endicott
NY, US
Agent
Lawrence R Fraley
Assignee
International Business Machines Corporation
NY, US
IPC
H05K 3/34
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