A selective etch process is performed so as to form {HEAD ~ self aligned contact openings} that extend through {TAIL ~ the pre metal dielectric film} and through the barrier layer in the core region 
extend through
A selective etch process is performed so as to form { HEAD ~ self aligned contact openings } that extend through { TAIL ~ the pre metal dielectric film } and through the barrier layer in the core region
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH