US Patent 7132337 Charge-trapping memory device and method of production

Charge-trapping regions are arranged beneath lower edges of the gate electrode separate from one another. Source/drain regions are formed in self-aligned manner with respect to the charge-trapping regions by means of a doping process at low energy in order to form shallow junctions laterally extending only a small distance beneath the charge-trapping regions. The self-alignment ensures a large number of program-erase cycles with high effectiveness and good data retention, because the locations of the injections of charge carriers of opposite signs are narrowly and exactly defined.