forming {HEAD ~ source/drain regions} in {TAIL ~ a semiconductor substrate}, wherein the source/drain regions define a channel region therebetween 
in
forming { HEAD ~ source / drain regions } in { TAIL ~ a semiconductor substrate } , wherein the source / drain regions define a channel region therebetween
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH