A semiconductor integrated circuit that includes thereon a flash memory and a plurality of MOS transistors using different power supply voltages is formed by a process in which a thermal oxidation process is applied to one of the device regions while covering the other device regions by an oxidation-resistant...http://www.google.de/patents/US7635653?utm_source=gb-gplus-sharePatent US7635653 - Method of fabricating a semiconductor circuit having a plurality of MOS transistors and flash memory
