Preferably, the edge portion defining {HEAD ~ the via opening} is greater in {TAIL ~ diameter} compared to a via bottom portion by about 10 percent to about 30 percent 
Preferably , the edge portion defining { HEAD ~ the via opening } is greater in { TAIL ~ diameter } compared to a via bottom portion by about 10 percent to about 30 percent
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH