METAL FILLER, LOW-TEMPERATURE-BONDING LEAD-FREE SOLDER AND BONDED STRUCTURE

摘要

Provided is a metal filler comprising a mixture of first metal particles with second metal particles, wherein the first metal particles are Cu-alloy particles containing Cu as the major component, which is an element being present at the highest ratio by mass, together with In and Sn; the second metal particles are Bi-alloy particles containing 40-70% by mass of Bi together with 30-60% by mass of one or more metals selected from among Ag, Cu, In and Sn; and the content of the second metal particles is 40-300 parts by mass per 100 parts by mass of the first metal particles. Also provided are a lead-free solder containing the aforesaid metal filler, a bonded structure formed by using the aforesaid lead-free solder, and a substrate to which a part provided with the aforesaid bonded structure is mounted.