Hybrid atomization method suitable for production of fine spherical lead-free solder powder

• Autorzy: Minagawa K. , Kakisawa H. , Takamori S. , Osawa Y. , Halada K.
• Konferencja: Proceedings of the 2nd Polish-Japanese Workshop on Materials Science "Materials for Sustainable Development in the 21st Century" 12-15 October 2005, Warsaw, Poland
• Języki publikacji: EN

Abstrakty

EN

In response to the problem of environmental protection, the electronic industry is studying the lead-free alloys as substitutes for lead-containing solder alloys. At the same time, with progress in electronic devices in recent years, smaller size and higher precision are strongly demanded in electronic board connections. Therefore, it is necessary to prepare fine powders of solder paste for these connections. To produce such lead-free solder balls, a novel powdermaking process, “hybrid atomization” that combines gas atomization and centrifugal atomization, was used. This technique produces very fine and spherical tin alloy powders with a mean diameter of about ten micrometers and very narrow size distribution with few satellites at low production cost. Taking a Sn-9mass%Zn alloy as an example, process experiments were carried out, and the effect of temperature, spray distance and disk rotating speed on the resultant powder properties were examined. The optimal processing conditions were determined from the results; the influences of the processing parameters on the properties of the obtained powders were quite different from those in the conventional atomization processes. The spherical powder with a mean diameter of 10.6 žm and a standard deviation of 1.3 ~ 1.7 was obtained in the determined optimum condition.

Słowa kluczowe

EN

ead-free solder; fine spherical powder; hybrid atomization

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2006
• Tom: Vol. 51,suppl.1
• Strony: 83--88
• Opis fizyczny: Bibliogr. 15 poz., rys.

Twórcy

autor

Minagawa K.

autor

Kakisawa H.

autor

Takamori S.

autor

Osawa Y.

autor

Halada K.

• Ecocirculation Processing Group, Ecomaterials Center, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba City, Ibaraki 305-0047, Japan, Tel.: [phone], Fax: [phone],

Bibliografia

• 1. European Commission (1997) End of life electrical and electronic equipment working paper. Directive General IV, Document E 3, 9, October 1997
• 2. European Commission (1998) End of life electrical and electronic equipment working paper, second draft.Directive General IV, 27 July 1998
• 3. Fuji T, Hirose A, Kobayashi K (2000) Microstructure and mechanical properties of microjoints with Sn-Ag lead free solders. In: Proc of the 7th Symp on Microjoining and Assembly Technology in Electronics, Yokohama, Japan,pp 211−216
• 4. Halada K, Suga H (1990) Theoretical investigation on parameters of centrifugal atomization of metal powder.Journal of the Japan of Powder and Powder Metallurgy 37;4:492−499
• 5. Kariya Y (2003) The influence of Ag concentration on shear fafigue properties of the Sn-Ag-Cu solder vamp for flip chip junction. Metal 73;7:635−639
• 6. Matsumoto S, Takashima Y (1983) Recent progress of liquid atomization technology. The Society of Chemical Engineers, Japan 47;9:540−543
• 7. McCormack M, Jin S, Kammlott GW, Chen HS (1993)New Pb-free solder alloy with superior mechanical Properties. Appl Phys Lett 63;1:15−17
• 8. Minagawa K, Halada K (2005) Production of metal fine powder. Patent No. 3511082, Japan
• 9. Nakahara Y, Ninomiya R, Matsunaga J, Takemoto T(1999) Mechanical properties and oint strength of Sn-3.5Ag-3In-xBi solders. In: 6th Symp on Microjoining and Assembly Technology in Electronics, Yokohama,Japan, pp 341−346
• 10. Shiya T (1972) Fine particle refinement by rotation disk.The Society of Chemical Engineers, Japan 36;1:10−16
• 11. Suga T (1999) Lead-free solder technique. The Nikkankogto Shmbun Ltd
• 12. Suganuma K (2003) Restriction in Europe and current state of technology for lead free solder. Metal 73;7:648−659
• 13. Tanazawa Y, Miyasaka Y, Umehara M (1959) On the filamentation of liquid by means of rotating discs (1st Report, Mode of filamentation of viscous liquid).Mechanical Engineers 25;156:879−888
• 14. Tanazawa Y, Miyasaka Y, Umehara M (1959) On the filamentation of liquid by means of rotating discs (2nd Report, Mode of filamentation of viscous liquid).Mechanical Engineers 25;156:888−897
• 15. Vianco PT, Frear DD (1993) Issues in the emplacement of lead-bearing solders. Jon − Journal of the Minerals Metals and Materials Society 45;7:14−19