International Business Machines Corporation

John Christopher Camp

Thomas R Miller

Ashwinkumar C Bhatt

Edmond Otto Fey

Edward Lee Arrington

Robert Jeffrey Day

Curtis Michael Gunther

Voya Rista Markovich

Michael Wozniak

John A Welsh

Subahu Dhirubhai Desai

Mary Beth Fletcher

Kenneth Lynn Potter

A process for removal of undesirable conductive material (e.g., catalyst material and seeped circuit material) on a circuitized substrate and the resultant circuitized substrates disclosed. Such process and resultant circuit effectively address the electrical shorting problems caused by nonremoval of the residual catalyst material and circuit material which has seeped under the residual catalyst material. The process includes the steps of: a) providing a catalyst layer (e.g., palladium and tin) having circuit pattern (e.g., copper) thereon; b) pretreating the catalyst layer and the circuit pattern (e.g., with a cyanide dip) for removal of undesirable portions of each which cause electrical leakage between circuit lines of the circuit pattern; c) oxidizing the catalyst layer and the circuit pattern (e.g., with chlorite, permanganate, hydrogen peroxide, or air at a temperature elevated above ambient conditions); and d) removing the undesirable portions of the catalyst layer and the undesirable portions of the circuit pattern (e.g., with a cyanide submersion). The resultant circuitized substrate includes a circuit pattern on a catalyst layer wherein undesirable portions of the catalyst layer and circuit pattern are completely removed between the circuit features of the circuit pattern so that electrical leakage between the circuit features does not occur.

Process for removal of undesirable conductive material on a circuitized substrate and resultant circuitized substrate

A technique is provided for forming a circuitized substrate which substantially reduces defects in a circuit board formed of multiple layers of dielectric material on each of which layers electrical circuitry is formed. Each layer of dielectric material is formed of two distinct and separate coatings or sheets or films of a photopatternable dielectric material which is photoformed to provide through openings to the layer of circuitry below and then plated with the desired circuitry including plating in the photoformed openings to form vias. In this way if there is a pin hole type defect in either coating or sheet of dielectric material, in all probability it will not align with a similar defect in the other sheet or coating of the dielectric layer, thus preventing unwanted plating extending from one layer of circuitry to the underlying layer of circuitry.

Method of reducing defects in I/C card and resulting card

A method for planarizing an exposed metal surface on a substrate is provided in which surface irregularities are eliminated. A photoresist layer is first removed from the substrate. Then a conformal planarizing head is placed in contact with the metal surface while chemical etchant essentially free of abrasives is supplied to an interface between the metal substrate and the planarizing head. The surface is then planarized until it is free of irregularties.

Method of surface finishes for eliminating surface irregularities and

Process for removal of undersirable conductive material on a circuitized

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Owego, NY, United States of America

John Christopher Camp