Radiation Effects on Programmed NROM Cells

NROM type non-volatile memories, having information charge stored in traps in silicon nitride layer, were subjected to different radiation sources in order to ascertain the radiation hardness. Fundamental device parameters, such as threshold voltage shift and current leakages were studied as function of the accumulated dose for gamma (60Co) and Boron ions irradiations to emulate real radiation environments for space and avionics applications. Radiation tolerance of NROM cells was registered with a pronounced degradation for doses exceeding 50 Krad and 1x1010 B/cm2 for gamma and Boron ions irradiations respectively.