2003 Volume 44 Issue 7 Pages 1316-1319
Considerable R&D efforts in last decade have identified several promising lead-free tin alloys for the replacement of lead-containing solders in microelectronic applications. However, it is difficult or uneconomical to produce high-quality solder balls industrially by means of conventional atomization methods. A new powder-making technology, Hybrid Atomization, was recently developed in order to inexpensively produce very fine uniform spherical powders with mean particle sizes of about or less than 10 μm. This new method effectively combines free-fall gas atomization with centrifugal atomization. For example, Sn–9 mass%Zn powders obtained by hybrid atomization show very fine particle size, spherical shapes, narrow particle size distributions, few satellites, and low oxidation. In this paper, the optimized production of lead-free tin solder powder by hybrid atomization was investigated, and the influences of the powder’s main processing parameters were discussed.