International Business Machines Corporation

Endicott Interconnect Technologies, Inc.

International Business Macjines Coporation

William John Rudik

Robert Maynard Japp

Bernd Karl Appelt

Kostantinos I Papathomas

Voya Rista Markovich

Thomas R Miller

William E Wilson

Lawrence Robert Blumberg

John Frank Surowka

Mark Vincent Pierson

Frank Daniel Egitto

David L Questad

Luis Jesus Matienzo

Son K Tran

Jean Dery

Luc Ouellet

Charles Ouellet

John Ulrich Knickerbocker

John M Lauffer

Anilkumar Chinuprasad Bhatt

James Warren Wilson

Gerald Walter Jones

David L Thomas

Ross William Keesler

Michael Wozniak

James W Fuller, Jr

Gregory A Kevern

Raymond A Phillips, Jr

George P Schmitt

John F Shipley

Kevin P Unger

Robert J Testa

Terry J Dornbos

David John Russell

David Brian Stone

Donald Seton Farquhar

David W Wang

Ramesh R Kodnani

William J Summa

Norman A Card

Stephen John Kosteva

Bernd Karl-Heinz Appelt

Leroy N Chellis

David Michael Passante

Jonathan Craig Whitcomb

Frank J Downes, Jr

Ball Grid Array packages having decreased adhesion of the BGA pad to the laminate surface and methods for producing same are provided.

Method of fabricating a BGA package having decreased adhesion

A method of making a circuitized substrate assembly in which two or more subassemblies are aligned and bonded together. The bonding, preferably using lamination, results in effective electrical connections being formed between respective pairs of conductors of the subassemblies in such a manner that the metallurgies of the conductors, and those of an interim metallic solder paste, are effectively mixed and the flowable interim dielectric used between the mating subassemblies is forced to flow to engage and surround the conductor coupling, without adversely affecting the electrical connection formed.

Method of making circuitized substrate with solder paste connections

A laminate circuit structure assembly is provided that comprises at least two modularized circuitized voltage plane subassemblies; optionally an interposer located between each of the subassemblies, and wherein the subassemblies and interposer, if present, are bonded together with a cured dielectric coating. The interposer comprises dielectric layers disposed about an internal electrically conductive layer.

Composite laminate circuit structure

Method and structure for an organic package with improved BGA life

A method for creating an impedance controlled printing wiring board, particularly the formation of a structure for high speed printed wiring boards incorporating multiple differential impedance controlled layers. Furthermore, disclosed is the provision of a method for producing an impedance controlled printed circuit wiring board. Also, there is the provision of a method for producing high speed printed wiring boards with multiple differential impedance controlled layers.

Method for producing an electronic package possessing controlled impedance characteristics

A simple, inexpensive, drillable, reduced CTE laminate and circuitized structures comprising the reduced CTE laminate, is provided. One embodiment of the reduced CTE laminate comprises: from about 40% to 75%, preferably from about 55% to 65%, by weight resin; from about 0.05% to 0.3%, preferably from about 0.08% to 0.10%, by weight curing agent; from about 25% to 60%, preferably from about 30% to 40%, by weight, woven cloth; from about 1% to 15%, preferably from about 5% to 10%, by volume, non-woven quartz mat. The method for making reduced CTE laminate and laminate structures comprises the following steps: providing non-woven quartz mat; providing a prepreg, preferably B-stage cured to not more than about 40%, preferably not more than 30% of full cure; sandwiching the non-woven quartz mat between two layers of prepreg, and reflowing the resin of the prepreg into the quartz mat.

Method for reducing coefficient of thermal expansion in chip attach packages

A method for fabricating a laminate circuit structure is provided. The method comprises: providing at least two modularized circuitized voltage plane subassemblies wherein each of the subassemblies comprise at least two signal planes having an external and internal surface disposed about an internal voltage plane; providing a dielectric material between the signal and voltage planes; and providing dielectric on each external surface of each signal plane; and providing a non-cured or partially cured curable dielectric composition between the subassemblies wherein the dielectric composition comprises, dielectric material that is of the same material as the dielectric material used in said subassemblies, aligning the subassemblies, and then laminating to cause bonding of the subassemblies.

Method of fabricating a laminate circuit structure

A printed circuit board for use in an electronic device package such as a ball grid array package or organic chip carrier package. This printed circuit board includes a glass-free dielectric for separating and insulating power cores, circuitry or plated through holes from each other to prevent shorts caused by a migration of conductive material along glass-based prepreg substrates.

Printed circuit boards for electronic device packages having glass free non-conductive layers and method of forming same

A process of fabricating a circuitized structure is provided. The process includes the steps of providing an organic substrate having circuitry thereon; applying a dielectric film on the organic substrate; forming microvias in the dielectric film; sputtering a metal seed layer on the dielectric film and the microvias; plating a metallic layer on the metal seed layer; and forming a circuit pattern thereon.

Process of fabricating a circuitized structure

A method and structure for conductively coupling a metallic stiffener to a chip carrier. A substrate has a conductive pad on its surface and an adhesive layer is formed on the substrate surface. The metallic stiffener is placed on the adhesive layer, wherein the adhesive layer mechanically couples the stiffener to the substrate surface and electrically couples the stiffener to the pad. The adhesive layer is then cured such as by pressurization at elevated temperature. Embodiments of the present invention form the adhesive layer by forming an electrically conductive contact on the pad and setting a dry adhesive on the substrate, such that the electrically conductive contact is within a hole in the dry adhesive. The electrically conductive contact electrically couples the stiffener to the pad. The curing step includes curing both the dry adhesive and the electrically conductive contact, resulting in the dry adhesive adhesively coupling the stiffener to the substrate. The electrically conductive contact may include an electrically conductive adhesive or a metallic solder. Additional embodiments of the present invention form the adhesive layer by applying an electrically conductive adhesive on the substrate, wherein after the stiffener is placed on the adhesive layer, the electrically conductive adhesive mechanically and electrically couples the stiffener to the surface of the substrate.

Electrical coupling of a stiffener to a chip carrier

A large liquid crystal display optical structure can be created by providing a transparent substrate with a dark mesh pattern disposed thereon. A means for optical scattering is over, adjacent, or surrounding the dark mesh, with a polarizer laminated to a smooth surface of the means for optical scattering.

LCD cover optical structure and method

A simple, inexpensive, drillable, reduced CTE laminate and circuitized structure comprising the reduced CTE laminate, is provided. The reduced CTE laminate comprises: from about 40% to 75%, preferably from about 55% to 65%, by weight resin; from about 0.05% to 0.3%, preferably from about 0.08% to 0.10%, by weight curing agent; from about 25% to 60%, preferably from about 30% to 40%, by weight, woven cloth; from about 1% to 15%, preferably from about 5% to 10%, by volume, non-woven quartz mat. The present invention also generally relates to a method for reducing the CTE of circuitized structures, and to methods for making reduced CTE laminate and circuitized structures comprising reduced CTE laminate. The method for making reduced CTE laminate and laminate structures comprises the following steps: providing non-woven quartz mat; providing a prepreg, preferably B-stage cured to not more than about 40%, preferably not more than 30% of full cure; sandwiching the non-woven quartz mat between two layers of prepreg, and reflowing the resin of the prepreg into the quartz mat. The method further comprises providing a resin volume percent, woven glass cloth volume percent and metal volume percent of the circuitized structure to be fabricated; selecting a desired CTE for the circuitized structure to be fabricated; and determining the amount of non-woven quartz or non-woven glass mat to be incorporated according to a formula. Optionally, the reduced CTE laminate is sandwiched between two layers of metal, preferably copper.

Structure for high speed printed wiring boards with multiple differential impedance-controlled layers

Reliability of circuit packaging while accommodating larger chips and increased temperature excursions is achieved by use of compliant pads only at the locations of connections between packaging levels, preferably between a laminated chip carrier and a printed circuit board. The invention allows the coefficient of thermal expansion of the chip carrier to be economically well-matched to the CTE of the chip and accommodation of significant differences in CTEs of package materials to be accommodated at a single packaging level. The compliant pads are preferably of low aspect ratio which are not significantly deflected by accelerations and can be formed on a surface or recessed into it. Connections can be made through surface connections and/or plated through holes. Connection enhancements such as solder wettable surfaces or dendritic textures are provided in a conductive metal or alloy layer over a compliant rubber or elastomer layer which may be conductive or non-conductive.

Circuit package having low modulus, conformal mounting pads

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Vestal, NY, United States of America

William John Rudik