{HEAD ~ A second dopant zone} with a doping of a second conductivity type is formed in {TAIL ~ a second region} of the semiconductor layer 
{ HEAD ~ A second dopant zone } with a doping of a second conductivity type is formed in { TAIL ~ a second region } of the semiconductor layer
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH