研究了总剂量辐照效应对0.35µm n型金属-氧化物-半导体(NMOS)器件热载流子测试的影响.试验结果表明：经过100 krad(Si)总剂量辐照后进行5000 s的热载流子测试， NMOS器件阈值电压随着总剂量的增大而减小，然后随热载流子测试时间的增加而增大，且变化值远远超过未经过总剂量辐照的器件；总剂量辐照后经过200 h高温退火，再进行5000 s的热载流子测试，其热载流子退化值远小于未高温退火的样品，但比未辐照的样品更明显，即总剂量辐照与热载流子的协同效应要超过两种效应的简单叠加.根据两种效应的原理分析，认为总剂量辐照感生氧化层陷阱电荷中的空穴与热电子复合减少了正氧化层的陷阱电荷，但辐照感生界面态俘获热电子形成负的界面陷阱电荷，表现为两者的协同效应模拟方式比单机理模拟方式对器件的影响更严重.%The equipment and devices which are long-time running in space are affected by space radiation effects and hot carrier injection effects at the same time which would reduce their optional times. Normally, the single mechanism test simulation method is used on the ground simulation test but the multi-mechanism effect affects the space equipments and devices, including total irradiation dose effect, hot carrier injection effect, etc. The total dose dependence of hot carrier injection (HCI) effect in the 0.35 µm n-channel metal oxide semiconductor (NMOS) device is studied in this paper. Three samples are tested under different conditions (sample 1# with total irradiation dose (TID) and HCI test, sample 2# with TID, annealing and HCI test, sample 3# only with HCI test). The results show that threshold voltage of NMOS device with 5000 s HCI test after 100 krad (Si) total dose radiation has been negatively shifted then positively during total dose irradiation test and HCI test, and the threshold is higher than that of the device without radiation test. But the threshold voltage shift of NMOS device with 5000 s HCI test and 200 h annealing test after TID test is higher than that of the devices without radiation test and lower than that of the devices without annealing test. That is, the parameters of NMOS device vary faster with the combined effects (including the total dose irradiation effect and HCI effect) than with single mechanism effect. It is indicated that the hot electrons are trapped by the oxide trap charges induced by irradiation effect and then become a recombination centre. And then the oxide trap charges induced by irradiation effect reduce and become negative electronic. The interface trap charges induced by irradiation effect are reduced and then increased it is because the electrons of hole-electron pairs in the Si-SiO2 interface are recombined by oxide traps in the oxide during the forepart of HCI test but then the electrons are trapped by interface traps in the Si-SiO2 interface because the electrons from source area are injected to interface during the HCI test. So the threshold voltage is positively shifted due to the negative oxide trap charges and interface trap charges. The association effect is attributed to the reduction of oxide traps induced by recombination with hot electrons and the increase of the interface traps induced by irradiation trapped hot electrons.
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