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:
Jun. 22, 1993
Filed:
Jul. 08, 1992
Kathleen L Covert, Kirkwood, NY (US);
Jennette E Kingsley, Vestal, NY (US);
David N Light, Friendsville, PA (US);
Richard A Schumacher, Endicott, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
Disclosed is a method of fabricating a microelectronic package, especially a microelectronic package having copper circuitization on a dielectric substrate. The method includes depositing copper on opposite surfaces of the package, and then depositing resist atop the copper. The resist is patterned, e.g., by photolithography or screening so that intended circuitization traces are covered by the resist. The exposed copper is etched, and the resist is stripped off of the unexposed copper. The process is characterized in that the etchant is upwardly sprayed onto a downwardly facing first surface of the package for half of the etching cycle, and then the package is rotated so that etchant is upwardly sprayed onto the downwardly facing second surface of the package.