International Business Machines Corporation

Ibm Canada Limited - Ibm Canada Limitee

Eric Duchesne

Michael A Gaynes

Kang-Wook Lee

Eric A Johnson

Luis Jesus Matienzo

James Robert Wilcox

David V Caletka

Valerie A Oberson

Isabelle Paquin

Jean Dery

Barry A Bonitz

Charles C Bureau

Simon Landry

Dominique Drouin

Aurore F M E Quelennec

Dragoljub Veljanovic

Hélène Frémont

Umar Shafique

Patrick R J Wilson

David Hirsch Danovitch

Sylvain E Ouimet

Julien Sylvestre

Timothy A Gosselin

Claude Blais

Gerald J Scilla

David Danovitch

Carbon nanotube-based multi-sensors for packaging applications and methods to form the carbon nanotube-based multi-sensors are capable of simultaneously measuring at least two measurands including temperature, strain, and humidity via changes in its electrical properties.

Carbon nanotube-based multi-sensor

An approach to provide an electronic assembly process that includes receiving at least one electronic assembly after a solder reflow process using a Sn-containing solder and a water-soluble flux. The approach includes baking the at least one electronic assembly in an oxygen containing environment and, then cleaning the at least one electronic assembly in an aqueous cleaning process.

Enhanced cleaning for water-soluble flux soldering

The invention relates to a composition of matter comprising a soldering flux, wherein the flux consists essentially of a combination of a fluxing agent and a solvent, and wherein the fluxing agent comprises a keto acid such as levulinic acid or acetylbutyric acid. The flux may also comprises an ester acid, or comprises a mixture of the keto acid with the ester acid. The solvent comprises a mixture of a tacky solvent with a non-tacky solvent. The invention also relates to a process comprising soldering at least two surfaces together, each of which comprises a metal area to which solder can adhere by employing the following steps in any order: applying solder to at least one of the metal areas, aligning the metal areas so that they are superimposed over one another, heating at least one of the areas to a temperature that comprises at least the melting temperature of the solder. The last step comprises joining the superimposed areas to one another. The process employs the flux composition operatively associated with the solder, and in one embodiment the invention comprises a mixture of the flux composition with powdered solder. In another embodiment, the process comprises IMS, C4 and C4NP processes and the solder comprises a lead free solder. The invention also comprises a product produced by the foregoing process or processes.

Flux composition and process for use thereof

A method of removing and/or reducing undesirable contaminants removes residues including graphitic layers, fluorinate layers, calcium sulfate (CaSO) particles, tin oxides and organotin, from a chip passivation layer surface. The method uses a plasma process with an argon and oxygen mixture with optimized plasma parameters to remove both the graphitic and fluorinated layers and to reduce the level of the inorganic/tin oxides/organotin residue from an integrated circuit wafer while keeping the re-deposition of metallic compounds is negligible. This invention discloses the plasma processes that organics are not re-deposited from polymers to solder ball surfaces and tin oxide thickness does not increase on solder balls. The ratio of argon/oxygen is from about 50% to about 99% Ar and about 1% to about 50% Oby volume. Incoming wafers, after treatment, are then diced to form individual chips that are employed to produce flip chip plastic ball grid array packages.

Method of removing metallic, inorganic and organic contaminants from chip passivation layer surfaces

The present invention is directed to soldering techniques and compositions for use therein. In one aspect, a flux composition is provided. The flux composition comprises a fluxing agent comprising organic acid, an organic tacking agent and an organic wetting agent. In another aspect, a soldering method for joining objects is provided comprising the following steps. A flux composition and a solder compound are applied to at least a portion of one or more of the objects. The flux composition comprises a fluxing agent comprising organic acid, an organic tacking agent and an organic wetting agent. The objects are then joined.

Flux composition and techniques for use thereof

A method for optimizing the manufacturing of interconnects in microelectronic packages in the presence of sources of process variability. The method can estimate the contribution of multiple parameter to the quality of the interconnects, enabling the optimization of the manufacturing process.

Method to optimize the manufacturing of interconnects in microelectronic packages

Electronically grounded heat spreaders are employed in connection with the dissipation of heat, which is generated by electronic devices, such as semiconductor chips. Also provided is a novel method for the adhesive fastening of metallic heat spreaders to semiconductor chips through the combined use of electrically conductive and non-conductive adhesive materials.

Electronically grounded heat spreader

An electronic structure, and associated method of fabrication, for coupling a heat spreader above a chip to a chip carrier below the chip. Initially provided is a substrate, a chip on a surface of the substrate and coupled to the substrate, and the heat spreader. Then a fillet of at least one adhesive material is formed on the chip and around a periphery of the chip. Additionally, the heat spreader is placed on a portion of the fillet and over a top surface of the chip. The fillet couples the heat spreader to the substrate. An outer surface of the fillet makes a contact angle of about 25 degrees with the surface of the substrate. The small contact angle not exceeding about 25 degrees prevents cracking of the substrate that would otherwise result from thermal cycling.

Adjusting fillet geometry to couple a heat spreader to a chip carrier

In a microelectronic chip package for which grounding and thermal dissipation is desired, a cover is provided having an opening which is aligned with a contact on the substrate connected to ground potential. The cover is connected to the electronic device and the ground contact. This invention provides for a method and electronic package to overcome the difficulties encountered when attempting to simultaneously attach a cover to two different surfaces with two different adhesives.

Grounding and thermal dissipation for integrated circuit packages

An electronic structure, and associated method of fabrication, for coupling a heat spreader above a chip to a chip carrier below the chip. Initially provided is a substrate, a chip on a surface of the substrate and coupled to the substrate, and the heat spreader. Then a fillet of at least one adhesive material is formed on the chip and around a periphery of the chip. Additionally, the heat spreader is placed on a portion of the fillet and over a top surface of the chip. The fillet couples the heat spreader to the substrate. An outer surface of the fillet makes a to contact angle of about 25 degrees with the surface of the substrate. The small contact angle not exceeding about 25 degrees prevents cracking of the substrate that would otherwise result from thermal cycling.

A method of making a flip chip package that maintains flatness over a wide temperature range and provides good heat dissipation is described. A laminate substrate is electrically connected to electrical contacts disposed on a chip and underfill material is applied between the soldered connections. A body, for example an uncured dielectric material, is applied to the chip, the laminate substrate, a thermally conductive member or combinations thereof, and thermally conductive member is disposed adjacent to the surface of the chip that is opposite the surface connected to the laminate substrate. The body is extruded between the chip and the thermally conductive member. The thickness of the thermally conductive member is determined by balancing the stiffness and the CTE of both the thermally conductive member and the laminate substrate, and the length and width of the thermally conductive member may vary but are at least the size of the corresponding length and width of the chip.

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Granby, Canada

Eric Duchesne