金属-氧化物-半导体场效应管辐射效应模型研究

基于氧化层陷阱电荷以及界面陷阱电荷的产生动力学以及辐射应力损伤的微观机理,推导出了金属-氧化物-半导体场效应管(MOSFET)中辐射应力引起的氧化层陷阱电荷、界面陷阱电荷导致的阈值电压漂移量与辐射剂量之间定量关系的模型. 根据模型可以得到:低剂量情况下,氧化层陷阱电荷与界面陷阱电荷导致的阈值电压漂移量与辐射剂量成正比;高剂量情况下,氧化层陷阱电荷导致的阈值电压漂移量发生饱和, 其峰值与辐射剂量无关,界面陷阱电荷导致的阈值电压漂移量与辐射剂量呈指数关系. 另外,模型还表明氧化层陷阱电荷与界面陷阱电荷在不同的辐射剂量点开始产生饱和现象, 其中界面陷阱电荷先于氧化层陷阱电荷产生饱和现象.最后,用实验验证了该模型的正确性. 该模型可以较为准确地预测辐射应力作用下MOSFET的退化情况.

A radiation degradation model of metal-oxide-semiconductor field effect transistor

Based on the production kinetics of oxide-trapped charge and interface-trapped charge and the microscopic mechanism of radiation damage, a model of post-irradiation threshold voltage drift due to oxide trap and interface trap as a function of radiation dose is proposed. This model predicts that the post-irradiation threshold voltage drift due to oxide trap and interface trap would be linear in dose at low dose levels. At high dose levels, the post-irradiation threshold voltage drift due to oxide trap tend to be saturated, its peak value has no correlation with radiation dose, and the post-irradiation threshold voltage drift due to interface trap has an exponential relationship with radiation dose. In addition, the model indicates that the oxide-trapped charge and the interface-trapped charge start a saturation phenomenon at different radiation doses, and the saturation phenomenon of oxide-trapped charge appears earlier than interface-trapped charge. Finally, the experimental results accord well with the model. This model provides a more accurate prediction for radiation damage in metal-oxide-semiconductor field effect transistor.