patterning {HEAD ~ the layer} of dielectric material to expose {TAIL ~ at least one portion} of the semiconductor substrate overlying the channel region 
to expose
patterning { HEAD ~ the layer } of dielectric material to expose { TAIL ~ at least one portion } of the semiconductor substrate overlying the channel region
OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH