The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 12, 1995
Filed:
Sep. 09, 1994
Ivan I Chobot, Whitby, CA;
John A Covert, Binghamton, NY (US);
Randy L Haight, Waverly, NY (US);
Keith D Mansfield, New Milford, PA (US);
Donald W Miller, Newark Valley, NY (US);
Reinaldo A Neira, Endicott, NY (US);
Alexander Petrovich, Endicott, NY (US);
Paul C Sviedrys, Great Neck, NY (US);
Louise A Tiemann, Endwell, NY (US);
Gerald A Valenta, Haw River, NC (US);
Thurston B Youngs, Jr, Vestal, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method of forming a multi-layer circuit board or card. The method includes the step of forming a plurality of conductive planes. The conductive planes include ground, signal, or power planes. At least one through hole is formed through at least one of the conductive planes. An electrically conductive material is deposited onto an inside surface of the at least one through hole to form a plated through hole. At least one thermal relief passage is formed at least in the at least one of the conductive planes for preventing the diffusion of heat throughout the circuit board or card during the securing or removal or chips or other components to the circuit board or card by heating the material deposited in the at least one through hole to a temperature above its melting point. The at least one thermal relief passage is located in the vicinity of the at least one through hole and is free from electrical connection therewith. An electrically insulating material is deposited on at least one side of each of the conductive planes. The planes are placed on top of each other such that a layer of electrically insulating material is located between each of the conductive planes. The conductive planes are joined together to form the multi-layer circuit board or card.