ELECTRON TRAPPING DURING IRRADIATION IN REOXIDIZED NITRIDED-OXIDE

Isochronal detrapping experiments have been performed following irradi ation under different gate biases in reoxidized nitrided oxide (RNO) M OS capacitors. These show electron trapping by the nitridation-induced electron traps at low oxide fields during irradiation. A difference i n the detrapping behavior of trapped holes and elections is observed, with trapped holes being detrapped at relatively lower temperatures co mpared to trapped electrons. Electron trapping shows a strong dependen ce on the magnitude of the-applied gate bias during irradiation but is independent of its polarity Conventional oxide devices, as expected, do not show any electron trapping during irradiation by the native ele ctron traps. Finally a comparison of the isochronal detrapping behavio r following irradiation and following avalanche injection of electrons has been made to estimate the extent Of electron trapping. The result s show that-electron trapping by the nitridation-induced electron-trap s does not play the dominant role in improving radiation performance O f RNO, though its contribution cannot be Completely neglected for low oxide-held irradiations.