Texas Instruments Corporation

Robert A Sabo

Donald Charles Abbott

David W West

Christopher M Sullivan

Raymond A Frechette

Robert M Fritzsche

Steve Smith

John E Cotugno

A method for the fabrication of a double-sided electrical interconnection flexible circuit () particularly useful as a substrate for an area array integrated circuit package. A copper matrix with studs () is pressed through a dielectric film () having a copper layer on the opposite surface, thereby forming an intermediate structure for a flex circuit with self-aligned solid copper vias in a one step process. The contacts are reinforced by plating both surfaces with a layer of copper, and conventional processes are used to complete the circuit patterning.

Method of fabricating flexible circuits for integrated circuit interconnections

A double sided electrical connection flexible circuit particularly useful as a substrate for an area array integrated package, and the method of fabricating the structure is described. A circuit having interconnections on one surface and solder ball contact pads on the second surface are interconnected by copper plated from a single surface in order to avoid entrapment of air pockets. In one embodiment, the conductive vias are formed from a copper film which extends from the solder ball contact pads, which may be indented, providing a well for solder balls in the contact pad.

Flex circuit substrate for an integrated circuit package

Growing community of inventors

Smithfield, RI, United States of America

Robert A Sabo