关键词: 
Geant4 /
RPP模型 /
灵敏体积 /
单粒子翻转 /
δ电子

摘要: 利用Geant4蒙特卡洛程序包， 基于RPP (Rectangular ParallelePiped Volume)模型构建SRAM器件单元的灵敏体积， 编写了重离子在器件材料中的输运程序和单粒子翻转截面计算方法， 得到了简化器件结构的单粒子翻转截面σ与线性能量转移LET的关系曲线， 计算得到的翻转LET阈值和饱和截面与实验结果基本一致。模拟获得了LET值为99.69 MeV/(cm^-2·mg)的Bi离子及LET值为69 MeV/(cm^-2·mg)的Bi离子和Xe离子在器件材料中产生的δ电子分布图像，讨论了δ电子分布对翻转截面的影响。 计算了灵敏体积中能量沉积与δ电子分布的关系，认为δ电子分布对单粒子效应的影响随着器件的特征尺寸减小将更加严重。In this paper, the sensitive volume of SRAMs was constructed based on RPP(Rectangular ParallelePiped Volume) model using the Monte-Carlo code Geant4. The interactions of heavy ion with materials and the SEU(Single Event Upset) cross section calculation method were presented in the program. The SEU crosssection curves with the linear energy deposition ware obtained. The SEU threshold value and saturation cross section were consistent with the testing data with heavy ions beam. The δ electrons distribution were different in the device material, which were generated by Bi ion with LETs of 99.67 MeV/(cm²·mg) and Bi ion, Xe ion with LETs of 69 MeV/(cm^-2·mg). These results indicate δ electrons distribution impacts on the SEU cross section. According to the relation of energy deposition in the sensitive volume, the δ electrons distribution have more and more important effect on the Single Event Effect with reducing the feature size of semiconductor devices.