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