a second gate electrode of a second MOS transistor of {TAIL ~ a second conductivity type} formed on {HEAD ~ said primary surface} of said substrate 
a second gate electrode of a second MOS transistor of { TAIL ~ a second conductivity type } formed on { HEAD ~ said primary surface } of said substrate
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH