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