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:
Aug. 11, 1992
Filed:
Jul. 12, 1991
Henri Lochon, Saintry-sur-Seine, FR;
Georges Robert, La Ferte-Alais, FR;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method of forming metal contact terminals (35) of a determined size having an insulating substrate (17) with a metal land (18) formed thereon and a passivating layer (19) provided with an opening exposing a part of the metal land by forming intermediate metal contact pad (33') in the contact opening, applying and patterning a photoresist, delineating the intermediate metal contact pad (33') using pattern (31) as an in-situ mask, depositing a lead-tin solder layer (34') over a metal mask to form a solder bump (34') on the final metal contact pad, and reflowing the solder to form a solder ball (34). Thereby achieving the metal contact terminal (35) at the contact pad site. The above method has applicability to the fabrication of contact terminals for high density/high count I/O connections for advanced semiconductor chips that are appropriate for flip-chip (C4) or face-down bonding thereof on metallized ceramic (MC) substrates.