COMPOUND ALLOY METAL BALL USED AS CONNECTOR OF ELECTRICAL/ ELECTRONIC CIRCUIT COMPONENT AND METHOD FOR MANUFACTURING THE SAME

• Main Authors: TAKEUCHI TAKAO, KAJITA OSAMU, YAKIDA YOSHINOBU, YOSHIMOTO MASAKAZU, OKUHAMA YOSHIAKI, NISHIDA MOTONORI, OBATA KEIGO, IMAE SHINYA
• Format: Patent
• Language: English
• Published: 13.05.2004
• Edition: 7
• Subjects: ALLOYS; APPARATUS THEREFOR; BASIC ELECTRIC ELEMENTS; CHEMISTRY; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; ELECTROFORMING; ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; FERROUS OR NON-FERROUS ALLOYS; METALLURGY; PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTIONOF COATINGS; SEMICONDUCTOR DEVICES; TREATMENT OF ALLOYS OR NON-FERROUS METALS

PROBLEM TO BE SOLVED: To comparatively inexpensively and stably provide compound alloy metal balls of a high melting point excellent as connectors of electrical/electronic circuit components. SOLUTION: The metal ball surfaces are provided with electroplating silver-copper alloy film layers and the silver content of the silver-copper alloy films is specified 5 to 97wt% and the film thickness to ≥0.5 μm. In addition, the metal balls are composed of single metal or alloy having the melting point higher than the melting point of the silver-copper alloy film layers. The metal balls which are minute, are excellent in sphericity and have uniform dimensional accuracy are produced by an equal liquid droplet spray process, plasma rotating electrode process or flushing process and thereafter the silver-copper alloy film layers of a uniform film thickness are formed by an electroplating process on the resultant metal ball surfaces. The compound alloy metal ball of the high melting point having excellent joining characteristics can thus be provided by taking advantage of the sphericity and dimensional accuracy of the workpiece metal balls. COPYRIGHT: (C)2004,JPO