Abstract: The present invention relates to a solution and to a method of treating copper surfaces, the copper surfaces being brought into contact with an acidic treatment liquid which contains hydrogen peroxide and at least one five-membered heterocyclic compound as well as additionally at least one microstructure modifying agent selected from the group comprising thioles A, disulfides B, sulfides C and thioamides D having the following respective general formulae: wherein R1 and R2=alkyl, alkenyl, aryl, aralkyl, especially benzyl, cycloalkyl and the derivatives thereof and R3=R1, R1—O, R1—S, amino or substituted amino, wherein R1 and R2 may especially be phenyl or substituted phenyl.

Abstract: Process to improve adhesion of dielectric materials to a metal layer, including providing an unpatterned metal layer having a first major surface; micro-roughening the first major surface to form a micro-roughened surface; and etching the metal layer to form a circuit pattern in the metal layer, in which the micro-roughening is carried out prior to the etching.

Abstract: The present invention relates to a solution and to a method of treating copper surfaces, the copper surfaces being brought into contact with an acidic treatment liquid which contains hydrogen peroxide and at least one five-membered heterocyclic compound as well as additionally at least one microstructure modifying agent selected from the group comprising thioles A, disulfides B, sulfides C and thioamides D having the following respective general formulae: 1

Abstract: A microelectronic package (10) is formed and includes an integrated circuit die (12) attached to a substrate (14) by a plurality of solder bump interconnections (16) to form a preassembly (18). The integrated circuit die (12) has an active face (20) that faces the substrate (14) and is spaced apart therefrom by a gap (22). The integrated circuit die (12) also includes a back face (24) opposite the active face (20). The substrate (14) includes a die attach region (26) and a surrounding region (28) about the integrated circuit die (12). The solder bump interconnections (16) extend across the gap (22) and connect the integrated circuit die (12) and the substrate (14). A mold (30) is disposed about the preassembly (18) such that the mold (30) cooperates with the substrate (14) to define a mold cavity (32) that encloses the integrated circuit die (12).

Abstract: A microelectronic package (10) is formed and includes an integrated circuit die (12) attached to a substrate (14) by a plurality of solder bump interconnections (16) to form a preassembly (18). The integrated circuit die (12) has an active face (20) that faces the substrate (14) and is spaced apart therefrom by a gap (22). The integrated circuit die (12) also includes a back face (24) opposite the active face (20). The substrate (14) includes a die attach region (26) and a surrounding region (28) about the integrated circuit die (12). The solder bump interconnections (16) extend across the gap (22) and connect the integrated circuit die (12) and the substrate (14). A mold (30) is disposed about the preassembly (18) such that the mold (30) cooperates with the substrate (14) to define a mold cavity (32) that encloses the integrated circuit die (12).

Abstract: An electroless immersion plating process for depositing a tin-bismuth plate onto a surface formed of copper or the like comprises immersing the surface into an acidic aqueous solution comprising a tin alkane sulfonate compound, preferably tin methane sulfonate, and a bismuth alkane sulfonate compound, preferably bismuth methane sulfonate. The solution also contains thiourea in an amount effective to reduce tin at the surface. The bismuth compound is added in an amount to produce a bismuth concentration that is less than about 1.0 gram per liter. Furthermore, the ratio of tin to bismuth in the solution is at least 30 to 1, and preferably at least 50 to 1. The process deposits a dense, adherent plate composed of a tin-bismuth alloy containing at least 50 weight percent tin and preferably containing greater than 70 weight percent tin, which plate is well suited for use in microelectronic soldering operations.

Abstract: An electroless immersion plating process for depositing a tin-bismuth plate onto a surface formed of copper or the like comprises immersing the surface into an acidic aqueous solution comprising a tin alkane sulfonate compound, preferably tin methane sulfonate, and a bismuth alkane sulfonate compound, preferably bismuth methane sulfonate. The solution also contains thiourea in an amount effective to reduce tin at the surface. The bismuth compound is added in an amount to produce a bismuth concentration that is less than about 1.0 gram per liter. Furthermore, the ratio of tin to bismuth in the solution is at least 30 to 1, and preferably at least 50 to 1. The process deposits a dense, adherent plate composed of a tin-bismuth alloy containing at least 50 weight percent tin and preferably containing greater than 70 weight percent tin, which plate is well suited for use in microelectronic soldering operations.

Abstract: In an electronic package, a solder connection for bonding faying surfaces is formed of tin-bismuth alloy comprising a tertiary metal, preferably gold or silver, in an amount effective to increase the melting temperature of the alloy and enhance mechanical properties of the connection at elevated temperatures typically encountered during operation. A process for forming the solder connection comprises applying a film of the tertiary metal onto at least one faying surface and thereafter applying tin-bismuth solder paste onto the film. Preferably, a plate of tin-bismuth alloy is first electroplated onto the faying surface, onto which the tertiary metal is plated. During heating to reflow the solder, the tertiary metal dissolves to produce a uniform liquid that forms the connection.

Abstract: A method for producing a coating composed of an electroless metal plate, such as a copper plate, tightly bonded to a polyimide layer comprises a multi-step cure of the polyimide layer carried out in combination with a palladium-catalyzed electroless deposition process. A solution of a polyamic acid compound that is the precursor for the desired polyimide resin in a vaporizable solvent is applied to a substrate and heated preferably to temperature below 250.degree. C., to form a soft-cured polyimide film. The film is immersed in an aqueous palladium-tin colloidal suspension to deposit the colloidal particles thereon, which particles are then activated to form palladium nuclei dspersed on the surface. The soft-cured film is then heated, preferably above about 250.degree. C., to vaporize residual solvent and form a hard-cured polyimide layer having the palladium nuclei dispersed on the surface.