International Business Machines Corporation

Egon Max Kummer

Peter Alfred Gruber

Steven Alan Cordes

Carlos Juan Sambucetti

James L Speidell

Stephen Roux

Arthur R Zingher

Thomas George Ference

Bernie Hernandez

A precise volume, precisely registerable carrier is provided for use with injection molding for producing integrated circuit bump contacts in the &ldquo;flip chip&rdquo; technology. A hemispherical cavity is produced by etching through and undercutting a registered opening into a transparent carrier. The hemispherical cavity has related specific volume and visible peripheral shape that permits simple optical quality control when the injection molding operation has filled the cavity and simple optical registration for fusing to the pads on the integrated circuit.

Etched glass solder bump transfer for flip chip integrated circuit devices

An apparatus and method utilize vacuum injected molding of a liquid in a plurality of mold cells for solidification therein. An injection head includes spaced apart vacuum and injection slots positionable atop a mold plate in flow communication with the mold cells therein. Relative axial sliding is effected between the injection head and the mold plate for sequentially evacuating gas from the mold cells using a continuous vacuum followed in turn by sequentially injecting into the evacuated mold cells the liquid from a continuous source thereof. Sliding of the injection head over the mold plate automatically provides self valving for sequentially evacuating and filling the mold cells from the same side of the mold plate. In a preferred embodiment, the vacuum and injection slots are linked together at the mold plate so that surface tension of the liquid restrains flow of the liquid from the injection slot to the vacuum slot while allowing gas flow therebetween for effecting the vacuum in the mold cells.

Apparatus and method for vacuum injection molding

A precise volume, precisely registerable carrier is provided for use with injection molding for producing integrated circuit bump contacts in the 'flip chip' technology. A hemispherical cavity is produced by etching through and undercutting a registered opening into a transparent carrier. The hemispherical cavity has related specific volume and visible peripheral shape that permits simple optical quality control when the injection molding operation has filled the cavity and simple optical registration for fusing to the pads on the integrated circuit.

Etched glass solder bump transfer for flip chip integrated circuit

Growing community of inventors

Croton on Hudson, NY, United States of America

Egon Max Kummer