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:
Feb. 21, 1995
Filed:
Apr. 19, 1994
Thomas P Gall, Endwell, NY (US);
Anthony P Ingraham, Endicott, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method of flip chip bonding an integrated circuit chip to a chip carrier. A high melting temperature composition, such as a binary Pb/Sn alloy, is deposited on contacts on, for example, the chip, and constituents of a low melting composition, such as Bi and Sn, are codeposited on contacts on, for example, the chip carrier. The chip and chip carrier are then heated. This causes the lower melting temperature composition, for example the Bi and Sn, to melt and form a low melting temperature alloy, such as a Bi/Sn alloy. The low melting alloy dissolves the higher melting composition, as Pb/Sn. This results in the formation of a solder bond of a low melting point third composition, such as a ternary alloy of Bi/Pb/Sn.