Also, {HEAD ~ the components} being attached to the substrate can be flip chip semiconductor dies or {TAIL ~ chip capacitors}, which typically require an underfilling operation after reflow 
Also , { HEAD ~ the components } being attached to the substrate can be flip chip semiconductor dies or { TAIL ~ chip capacitors } , which typically require an underfilling operation after reflow
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH