removing the dielectric layer in {HEAD ~ the area} of {TAIL ~ the opening} of the mask to obtain the recess 
of
removing the dielectric layer in { HEAD ~ the area } of { TAIL ~ the opening } of the mask to obtain the recess
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH