Here is some data to compare the relative spread of indium based alloys on copper. Notice the difference between the old and new lots of 90In/10Ag. One lot was quite old and agitated – although the wetting was still very good compared to fresh 99.999% indium.
Pure indium is used quite often for specialty flip-chip bumping, although you may want to consider an In/Ag alloy. In addition to increased wetting, 3-10% Ag strengthens the indium alloy to resist creep.
Posted by Jim Hisert on March 10th, 2008 at 5:12 PM
