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