{TAIL ~ A combined solder alloy layer} composed of a combination of intermetallic compounds, one of tin and the solder alloy making {HEAD ~ layer}, and one of tin and the UBM layer, is formed by heating and melting 
{ TAIL ~ A combined solder alloy layer } composed of a combination of intermetallic compounds , one of tin and the solder alloy making { HEAD ~ layer } , and one of tin and the UBM layer , is formed by heating and melting
TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH