International Business Machines Corporation

Nelson P Franchak

Charles Gerard Woychik

Kishor V Desai

Robert H Katyl

Harold Kohn

Vilakkudi G Veeraraghavan

Tamar A Sholtes

Joseph Funari

Joseph G Ameen

Peter Bakos

Russell E Darrow

John Rasile

Dennis L Rivenburgh

Endwell

Method and apparatus are disclosed for mounting a flexible film semiconductor chip carrier on a second level electronic package. The resulting electronic packaging structure includes electrically conductive spacers, such as solder balls or solder coated copper balls, which electrically interconnect outer lead bonding pads on the flexible film semiconductor chip carrier and corresponding bonding pads on the second level electronic package, and which physically support the flexible film of the semiconductor chip carrier substantially in a plane above the surface of the second level electronic package. This electronic packaging structure is made using a special assembly fixture comprising a base plate, a pressure insert with a resilient member, and a top plate. The flexible film semiconductor chip carrier with the spacers attached thereto is placed over the resilient member of the pressure insert which is clamped together with the second level electronic package between the top and base plates. Then, this assembly is heated to reflow the solder of the spacers, and the assembly fixture is disassembled,; leaving the flexible film semiconductor chip carrier mounted on the second level electronic package with the flexible film of the carrier having a planar geometry as desired.

Method and apparatus for mounting a flexible film semiconductor chip

Method and apparatus are disclosed for mounting a flexible film semiconductor chip carrier on a second level electronic package. The resulting electronic packaging structure includes electrically conductive spacers, such as solder balls or solder coated copper balls, which electrically interconnect outer lead bonding pads on the flexible film semiconductor chip carrier and corresponding bonding pads on the second level electronic package, and which physically support the flexible film of the semiconductor chip carrier substantially in a plane above the surface of the second level electronic package. This electronic packaging structure is made using a special assembly fixture comprising a base plate, a pressure insert with a resilient member, and a top plate. The flexible film semiconductor chip carrier with the spacers attached thereto is placed over the resilient member of the pressure insert which is clamped together with the second level electronic package between the top and base plates. Then, this assembly is heated to reflow the solder of the spacers, and the assembly fixture is disassembled, leaving the flexible film semiconductor chip carrier mounted on the second level electronic package with the flexible film of the carrier having a planar geometry as desired. The spacers may be attached to the flexible film semiconductor chip carrier using a special template having a pattern of openings corresponding to the pattern of outer lead bonding pads on the flexible film semiconductor chip carrier.

A structure comprising on a substrate successive layers of metal circuitry having therebetween as a dielectric a cured polyimide composition containing a polyimide and aluminum oxide or zinc oxide or mixtures thereof. The structure is produced by a method including the following process steps:

Structure containing a layer consisting of a polyimide and an organic

A method for reducing the concentration of carbonate in an aqueous solution which includes contacting the aqueous solution with a strongly basic ion-exchange resin.

Reducing carbonate concentration in aqueous solution

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Binghamton, NY, United States of America

Nelson P Franchak