In a low voltage drive circuit section of a semiconductor integrated circuit, the gate oxide films are approximately 250 .ANG., and a low voltage N-channel IGFET and a low voltage P-channel IGFET are operable at high speed and driven at a low voltage. In a high voltage driven circuit section, the gate...http://www.google.com/patents/US5495122?utm_source=gb-gplus-sharePatent US5495122 - Insulated-gate semiconductor field effect transistor which operates with a low gate voltage and high drain and source voltages
