International Business Machines Corporation

Daniel C Van Hart

Luis Jesus Matienzo

Frank Daniel Egitto

David L Questad

Edmond Otto Fey

Rajinder S Rai

John Steven Kresge

Francis Joseph Downes, Jr

Ronald A Kaschak

Gerald G Advocate, Jr

William Louis Brodsky

Lawrence P Lehman

Ralph S Paonessa

Leann G Keim

Cynthia J Moring

An electronic structure including a metallic interlocking structure for bonding a conductive plated layer to metal surface, and a method of forming the electronic structure. The method provides a substrate having a metallic sheet within a dielectric layer. The metallic sheet includes a metal such as copper. An opening in the substrate, such as a blind via, is formed by laser drilling through the dielectric layer and partially through the metallic sheet. If the opening is a blind via, then the laser drilling is within an outer ring of the blind via cross section using a laser beam having a target diameter between about 20% and about 150% of a radius of the blind via cross section. A surface at the bottom of the opening, called a &ldquo;blind surface,&rdquo; includes a metallic protrusion formed by the laser drilling, such that the metallic protrusion is integral with a portion of the blind surface. The metallic protrusion includes the metal of the metallic sheet and at least one constituent element from the dielectric layer. The metallic protrusion is then etched to form a metallic interlocking structure that is integral with the portion of the blind surface. The metallic interlocking structure includes discrete metallic fibers, with each metallic fiber having a curved (or curled) geometry. Each metallic fiber has its own unique composition that includes the metal, at least one constituent element of the dielectric layer, or both.

Formation of a metallic interlocking structure

A congruence between the element that provides an electrical conductive path in a component of micron dimensions and an imaging of that element provides a basis for predicting the effectiveness and the consistency in the functioning of the element in an actual operating environment. The element is formed first into a sandwich whereby the operating end is deformed against a light transparent surface. By directing a beam of light into the end of that light transparent surface, the asperity of the operating end produces a light scattering effect that is imaged by microscopic optics that is located facing the operating end.

Technique for imaging electrical contacts

A metal alloy solder ball comprising a first metal and a second metal, the first metal having a sputtering yield greater than the second metal. The solder ball comprises a bulk portion having a bulk ratio of the first metal to the second metal, an outer surface, and a surface gradient having a depth and a gradient ratio of the first metal to the second metal that is less than the bulk ratio. The gradient ratio increases along the surface gradient depth from a minimum at the outer surface. The solder ball may be formed by the process of exposing the ball to energized ions of a sputtering gas for an effective amount of time to form the surface gradient.

Solder ball with chemically and mechanically enhanced surface properties

Metallic interlocking structure

A process for altering surface properties of a mass of metal alloy solder comprising a first metal and a second metal. The process comprises exposing the mass to energized ions to preferentially sputter atoms of the first metal to form a surface layer ratio of first metal to second metal atoms that is less than the bulk ratio. The solder may be located on the surface of a substrate, wherein the process may further comprise masking the substrate to shield all but a selected area from the ion beam. The sputtering gas may comprises a reactive gas such as oxygen and the substrate may be an organic substrate. The process may further comprise simultaneously exposing the organic substrate to energized ions of the reactive gas to roughen the organic substrate surface.

Enhanced solder surface and process for chemically and mechanically enhancing solder surface properties

Process for chemically and mechanically enhancing solder surface

Disclosed is a method of fabricating a microelectronic circuit package. The circuit package has a reinforced fluorocarbon polymer dielectric. According to the disclosed process, vias or through holes are formed in the composite by a process that leaves debris. The debris in the formed vias or through holes is reflowed in order to smooth the via and through hole walls for subsequent plating.

Removal of excimer laser debris using carbon dioxide laser

Disclosed is a method of fabricating a microelectronic package, especially a microelectronic package having gold plated copper circuitization on a polyimide substrate. The method includes the steps of forming a pattern of copper circuitization on the selected portions of the polyimide substrate, and thereafter depositing a gold thin film of selected portions of the copper circuitization layer. The gold thin film is electrodeposited from an electrodeposition solution of KAu(CN).sub.2, K.sub.2 HPO.sub.4, and KH.sub.2 PO.sub.4, modified by the addition of an effective amount of NH.sub.4.sup.+.

Gold plating bath additives for copper circuitization on polyimide

Growing community of inventors

Conklin, NY, United States of America

Daniel C Van Hart