电离总剂量对纳米SRAM器件单粒子翻转敏感性的影响

电离总剂量（TID）与单粒子效应（SEE）是纳米SRAM器件在航天应用中的主要威胁。随着CMOS工艺的进步，两种辐射效应在纳米SRAM器件中的协同效应出现了一些新现象，有必要进一步开展深入研究。利用γ射线以及不同种类重离子对两款纳米SRAM器件开展了辐照实验，研究了不同辐照参数、测试模式以及数据图形条件下，电离总剂量对单粒子翻转（SEU）敏感性的影响。研究结果表明，γ射线辐照过后，存储单元中反相器开关阈值减小，漏电流增大，导致SRAM存储单元抗翻转能力降低，SEU截面有明显增大；未观察到"印记效应"，数据图形对测试结果没有明显影响；多位翻转（MBU）比例无明显变化。

Impact of Total Ionizing Dose on Single Event Upset Sensitivity of Nano-SRAMs Devices

Total ionizing dose (TID) and single event effect (SEE) are both the main threats to nano-SRAMs devices in space application. With the development of CMOS technology, some new phenomena were observed during studying the synergistic effect between TID and SEE on nano-SRAMs. γ ray and heavy ion irradiations were performed to investigate the impact of total ionizing dose on single event upset (SEU) sensitivity of SRAMs. The influence of irradiation parameters, test modes and data patterns on synergistic effect were studied. The results showed that γ ray irradiation led to the decrease of threshold voltage and the increase of leakage current of inverters, which reduced the SEU hardness of SRAMs. Meanwhile, the SEU cross section increased compared with that of non-TID irradiated devices. There was no significant change in the percentage of multiple-bit upset (MBU). No "imprint effect" was observed. Data pattern applied in TID and SEE tests had no influence on the test results of SEU cross section.