0.13微米射频SOI器件的总剂量辐射效应机理研究

RF (Radio Frequency) devices have been widely used in space communications. However, with the development of aerospace engineering to deep space, the radiation-induced degradation of key parameters (cut-off frequency-ft, maximum oscillation frequency-fmax, ect.) of RF devices has serious effects on the stability of the space communications. Silicon-on-insulator (SOI) technology, which adopts fully dielectrically isolation, has superior performance for immunity to single event effects. Furthermore, the low insertion loss of RF signal of RF SOI devices can effectively improve the accuracy of space communications. Nevertheless, due to the radiation-induced charge trapping in the buried oxide (BOX) of SOI devices, the total-dose tolerance of SOI devices is weakened. The research on the mechanism of total dose effect in RF SOI devices of 0.13 µm technology is carried out in this project. Starting from the mechanism of ionized charge generation, trapping, and release in RF SOI devices, the impact law of the captured charges on the parasitic effect of RF SOI devices is studied. Focusing on the influence mechanism of the captured charges on the static and frequency characteristics of RF SOI devices, the total dose degradation laws of key parameters (ft, fmax, etc.) are summarized. Ultimately, effective radiation hardening techniques for total-dose-tolerated RF SOI devices are proposed, which can enhance the accuracy of the data processing of RF chip in the radiation environment, and thus to improve the stability of the space communication system and promote the applications of SOI technology in radiation tolerance field of National Defense

射频器件广泛应用于空间通信，随着航天工程向深空发展，辐射效应导致射频器件截止频率ft、最大振荡频率fmax等关键参数退化，严重影响空间通信的稳定性。SOI技术采用全介质隔离，具有优越的抗单粒子性能，同时射频信号插入损耗小，能有效提高空间通信的准确性，但是SOI器件的隐埋氧化层能俘获辐射电离电荷，减弱了SOI器件的抗总剂量特性。本项目开展0.13微米工艺射频SOI器件的总剂量辐射效应机理研究，从射频SOI器件的电离电荷产生、俘获及释放机理出发，研究俘获电荷对射频SOI器件寄生效应的影响规律，重点研究俘获电荷对射频SOI器件静态及频率特性的影响机理，总结ft、fmax等射频SOI器件关键参数的总剂量辐射退化规律。最终提出有效的抗辐射SOI射频器件加固方法，增强辐射环境下射频芯片数据处理的准确性，从而提高空间测控系统的稳定性，推动SOI技术在国防抗辐射领域的应用。

课题在模拟计算、器件测试、理论分析和工艺验证四个方面展开，通过对0.13微米射频SOI器件在总剂量辐照环境下的测试、验证及分析、研究了总剂量辐射导致的电离电荷在射频 SOI 器件栅氧化层、浅沟槽隔离（STI）及隐埋氧化层的产、俘获及释放机理。得到了总剂量辐射俘获电荷对射频SOI器件频率特性的影响机理：栅氧化层总剂量辐射效应产生的界面态增大了栅源、栅漏电容的寄生。寄生漏电通道、增长的关态漏电和栅、漏、STI边角区域的陷阱电荷会导致沟道电阻和寄生电容增加，造成电路的阻抗失配进而增加SOI 射频电路中的性能退化，导致跨导 gm 以及截止频率ft退化。基于实验结果给出了射频SOI器件抗辐射加固的方法：1、采用抗总剂量辐照器件加固结构设计；2、减薄栅氧化层的厚度；3、减薄前沟槽隔离的边角区域；4、改进工艺，使用高K栅极电介质。以上方法可以实现射频SOI器件的抗辐射工艺器件的优化，增强辐射环境下射频芯片数据处理的准确性，从而提高空间测控系统的稳定性，推动SOI技术在抗辐射领域的应用。