International Business Machines Corporation

Claude Blais

Kang-Wook Lee

David Hirsch Danovitch

Sylvain E Ouimet

Pedro A Chalco

Eric Duchesne

Pierre M Langevin

Louis-Marie Achard

Alain Warren

Gerald J Scilla

Michel Robert

Julie Nadeau Filteau

Robert L Toutant

Jean-Francois Garneau

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

Ink jet printing apparatus is employed to form a non-polar ink stop line around a chip site on the polar surface of an organic laminate substrate. The non-polar ink stop line acts to confine polar liquid flux from spreading after application of the flux to the chip site prior to chip joining. Excessive flux spreading results in insufficient flux being present at the chip site for the formation of good electrical connections during solder reflow upon chip joining.

Control of flux by ink stop line in chip joining

The disclosed invention provides for a method of manufacturing solder columns for particular use in attaching substrates to a printed circuit board. The method results in columns of homogeneous composition and thus overcomes problems associated with the phenomena of segregation. The method includes the steps of forming particles of the metal composition to be used for the columns from a molten source of the composition. The solid particles are then formed into segments of homogeneous composition by drawing ingots of the composition into wire and severing the wire into segments.

Method of manufacturing wire segments of homogeneous composition

A method for encapsulating a semiconductor chip. The method includes the steps of first positioning a chip over a laser-curing cavity, and then dispensing a predetermined amount of encapsulant over the chip. Sequential steps include synchronizing a firing of a laser pulse immediately after the dispensing step, and curing the encapsulant by conducting heat generated by the laser pulse, through the chip.

Semiconductor chip packaging method which heat cures an encapsulant

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Granby, Canada

Claude Blais