MRAM的辐射效应分析及加固方法简述

Analysis of the effects of radiation on MRAMs and corresponding hardening techniques

摘要: 回顾从首款商用磁随机存取存储器（MRAM）芯片面世以来国际上对MRAM芯片辐射效应的研究；总结MRAM总剂量电离效应和单粒子效应辐照试验研究结果，以及辐射效应导致MRAM读写错误的物理机制；分析辐射效应对磁性隧道结结构和性能的影响，并指出MRAM应当针对外围电路、存储单元晶体管和磁性隧道结等处不同类型辐射效应进行对应的抗辐射加固；最后从材料和工艺方面简要介绍MRAM加固方法。

Abstract: This paper reviews the international studies of the space radiation effects on MRAMs since the emergence of the first commercial MRAM chip. Firstly, the results of the total ionizing dose effect (TID) testing, the single event effect (SEE) testing on MRAM chips and the physical mechanism of the W/R errors caused by the radiation effect are summarized and analyzed. Then, the radiation effects on the magnetic tunnel junction (MTJ) is analyzed. Moreover, it is pointed out that the corresponding radiation hardening techniques should be implemented for different types of radiation effects at various sensitive nodes such as the periphery circuits, the storage cell, and the MTJs. Finally, some radiation hardening techniques for MRAM are introduced briefly from the aspects of materials and processes.