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