Quantitative characterization of ion-induced SiO₂/Si interface traps by means of MeV He single-ion irradiation

The dependencies of MeV He single-ion-induced interface traps on oxide thickness and oxide electric fields E_ox during irradiation was investigated quantitatively with a single-ion microprobe. Under a negative electric field, the number of interface traps induced by a single ion becomes constant at about 0.1 regardless of both the oxide thickness and oxide electric field. Under a positive electric field, the generation rate of interface traps per ion for thicker oxide metal–oxide–semiconductor field-effect transistors (MOSFETs) is greater than that for thinner oxide MOSFETs. We also found that the generation rates increase with dependence on the oxide electric field of E_ox^0.2, regardless of the oxide thicknesses. The field dependence of interface traps under a positive electric field was found to be very similar to that of oxide trapped holes. The causes of this dependence are discussed comprehensibly. © 1999 American Institute of Physics.