A drain region and a source/base region are formed in the semiconductor substrate adjacent the first gate structure and {HEAD ~ a cathode region} is formed in {TAIL ~ the semiconductor substrate} adjacent the second gate structure 
is formed in
A drain region and a source / base region are formed in the semiconductor substrate adjacent the first gate structure and { HEAD ~ a cathode region } is formed in { TAIL ~ the semiconductor substrate } adjacent the second gate structure
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH