A ball grid array can then be used to connect the signal contacts and ground at the second surface of {HEAD ~ the substrate} with {TAIL ~ a circuit board} 
with
A ball grid array can then be used to connect the signal contacts and ground at the second surface of { HEAD ~ the substrate } with { TAIL ~ a circuit board }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL