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:
Nov. 20, 2001
Filed:
May. 24, 1999
Abstract
A method for manufacturing a chip scale package comprises preparing a tape wiring board that includes a polyimide tape having top and bottom surfaces, Cu traces formed on the bottom surface of the tape, a window formed in the tape to enable the Cu traces to be connected to a semiconductor chip attached below the board, multiple connection holes formed in the tape to expose portions of the Cu traces therethrough and define solder ball mounting pads, and an elastomer chip carrier attached to the bottom surface of the tape. The method includes applying either a pre-flux or a cover sheet over the solder ball mounting pads. The pre-flux and the cover sheet each prevents the solder ball mounting pads being plated with gold. This, in turn, prevents the formation of intermetallic compounds in the solder balls so that the bond strength between the solder balls and a pad to which they attach is improved.