高能质子辐照导致电荷耦合器件性能退化研究

Performance Degradation of Charge Coupled DevicesIrradiationed by High Energy Proton

针对空间环境中高能质子辐射导致电荷耦合器件(CCD)性能退化评估问题,开展能量高于60 MeV的质子辐照试验,考察了CCD的重要性能参数暗电流和电荷转移效率受质子辐照的退化情况及质子辐照后CCD的热像素产生情况。研究表明:高能质子辐照导致CCD性能退化的敏感参数包括暗电流、电荷转移效率和热像素;对于60 MeV和100 MeV的质子能量,当辐照注量达到5×10^(10) cm^(-2)时,暗电流和电荷转移效率出现了一定的退化,更加显著的退化表现在热像素的产生。分析发现,60 MeV和100 MeV质子辐照导致暗电流和电荷转移效率的退化可通过NIEL进行等效,而热像素产生则不能等效。因此,在进行高能质子辐照导致CCD性能退化评估时,需重点考察热像素产生情况,且应针对实际应用的辐射环境,使用合适的质子能量进行更具针对性的辐照试验。

The evaluation of CCD performance degradation caused by high-energy proton radiation in space environment is studied.Proton irradiation experiments with energy higher than 60 MeV are carried out.The degradations of parameters such as dark current,charge transfer efficiency,and hot pixels of CCD after proton irradiation are measured.When the irradiation fluence is 5×10^(10)cm^(-2) and the proton energy is 60 MeV and 100 MeV respectively,the dark current and charge transfer efficiency of CCD degrade to a certain extent.However,the more significant degradation is the generation of a large number of hot pixels.It is found that the degradation of dark current and charge transfer efficiency caused by 60 MeV and 100 MeV proton irradiation can be equivalent by NIEL equivalent method,while the generation of hot pixels can not be equivalent.Therefore,when evaluating CCD performance degradation caused by high-energy proton irradiation,it is necessary to focus on the generation of CCD hot pixels,and adopt appropriate proton energy for irradiation test according to the practical radiation environment.