总剂量辐射对65 nm NMOSFET热载流子敏感参数的影响

Degradation of Hot Carrier Sensitivity Caused by Total Dose Irradiation in 65 nm NMOSFET

为了研究总剂量辐射对纳米MOS晶体管热载流子效应的影响,对65nm体硅工艺的NMOS器件进行了总剂量辐射和热载流子试验,对比了辐射前后不同宽长比器件的跨导、栅极泄漏电流、线性饱和电流等电参数。结果表明,MOS器件的沟道宽度越窄,热载流子效应受辐射的影响越显著,总剂量辐射后热载流子效应对器件的损伤增强。分析认为,辐射在STI中引入的陷阱电荷是导致以上现象的主要原因。该研究结果为辐射环境下器件的可靠性评估提供了依据。

The effects of total dose irradiation on the subsequent hot carrier effect of 65 nm NMOS devices were investigated.By testing and comparing the transfer characteristic curves,the transconductance,gate leakage current and linear saturation current,and other electrical parameters of the narrow and wide channel NMOS devices before and after irradiation were studied.The effects of total dose irradiation on the hot carrier effect were analyzed.The results showed that the narrow channel transistor was affected more by irradiation than wide channel device.The combined effect of total dose irradiation and hot-carrier stress on gate leakage current was greater than that of each single effect.It was concluded that the trap charge introduced in the STI was the reason for the increase of hot carrier degradation.The results provided the basis for reliability evaluation of devices in radiation environment.