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:
Apr. 28, 1998
Filed:
Apr. 09, 1997
Soyeon P Laub, Los Angeles, CA (US);
Michael J Little, Woodland Hills, CA (US);
James A Foschaar, Thousand Oaks, CA (US);
Hugh L Garvin, Malibu, CA (US);
Michael W Yung, Los Angeles, CA (US);
Hughes Aircraft Company, , US;
Abstract
A method for fabricating resilient z-axis contacts to electrically interconnect IC wafers or MCMs in 3-D integrated circuits uses photolithography to provide larger carrier sizes, higher contact densities by decreasing the spacing, smaller contact footpads, and precise control of the contact's shape and position. The contacts are fabricated by forming photoresist patterns on the carrier's top and bottom surfaces that are initially rectangular, and then reflowing the photoresist materials to provide smooth surfaces suitable for forming the metal contacts, and depositing metal layers over the respective patterns. Second photoresist patterns are formed over respective metal layers to conform with the contact's shape, the metal is etched away according to the pattern, and the photoresists are removed such that the remaining metalization forms a resilient z-axis contact that is attached to the carrier and extends therefrom with a predetermined shape.