A second semiconductor well of {HEAD ~ the first conductivity type} is disposed in {TAIL ~ the first semiconductor well} 
A second semiconductor well of { HEAD ~ the first conductivity type } is disposed in { TAIL ~ the first semiconductor well }
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL