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. 01, 2004
Filed:
Nov. 14, 2002
Krishna G. Sachdev, Hopewell Junction, NY (US);
James N. Humenik, LaGrangeville, NY (US);
Chon Cheong Lei, Poughkeepsie, NY (US);
Glenn A. Pomerantz, Kerhonkson, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A process of cleaning of objects that relate to semiconductor fabrication processes, such as, for example, conductive paste screening in the production of multilayer ceramic substrates and composite solder paste by stencil printing in electronic circuit assembly. Specifically, the process removes a metal/polymer composite paste from screening masks and associated paste making and processing equipment used in printing conductive metal pattern onto ceramic green sheet in the fabrication of semiconductor packaging substrates. The process also cleans solder paste residue from stencil printing equipment used in electronic module assembly surface mount technology for SMT discretes, solder column attachment, and BGA (Ball Grid Array) attachment on ceramic chip carrier or for screening solder paste onto printed circuit board. More particularly, paste residue is cleaned from metal, ceramic, and plastic substrates by a non-alkaline semi-aqueous cleaning method employing high boiling propylene glycol alkyl ether or mixtures of propylene glycol alkyl ether and propylene glycol solvents.