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:
May. 04, 1999
Filed:
Sep. 20, 1996
Applicant:
Inventor:
Robert T Trabucco, Loa Antos, CA (US);
Assignee:
LSI Logic Corporation, Milpitas, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ; H01L / ;
U.S. Cl.
CPC ...
438615 ; 438661 ; 438662 ; 257738 ; 29843 ;
Abstract
A fluxless method for fusing preformed solder balls to contact pads on a semiconductor package substrate wherein a masking plate having one or more vertical holes corresponding to the contact pads is placed over the package substrate, oxide-free solder balls are placed in the holes, the assembly is preheated to a temperature less than the melting point of the solder, and an energetic beam is directed onto the preformed solder balls to melt them and fuse them to the contact pads.