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