High melting point copper-gold-tin brazing alloy for chip carriers

US4634638A · kind A · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Norman G. Ainslie · Croton-on-Hudson, US
• Joseph M. Harvilchuck · Billings, US
• Mario J. Interrante · New Paltz, US
• William J. King · Reading, US
• Paul H. Palmateer · Wappingers Falls, US
• John F. Sullivan · Mission Hills, US

Key dates

• Filing date: Dec 17, 1981
• Grant date: Jan 6, 1987
• Expiry date: Dec 17, 2001

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/12889
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

Brazing of elements to electronic chip carrying substrates requires brazing materials strong at high temperatures used to remove and replace chips. Flanges and pins are brazed with Au:Sn brazing alloys modified during brazing by addition of copper to the brazing material to promote formation of the higher melting point .beta. phase of the alloy and a Group VIII metal to draw Sn out of the melt by gettering, also to promote formation of the .beta. phase of the alloy and to thicken the braze material. A copper preform is plated with Ni and juxtaposed with surfaces to be brazed and the brazing material to add Ni and copper to the melt.