基于脉冲激光定位的SRAM单粒子闩锁事件率预估

器件单粒子闩锁效应(SEL)预估方法一般是建立在只有一个敏感体积单元的长方体(RPP)模型上,静态随机存储器(SRAM)单粒子闩锁敏感区的定位试验结果表明敏感体积单元不仅有一个.利用脉冲激光定位SRAM K6R4016V1D单粒子闩锁效应敏感区的试验结果对器件在轨SEL事件率进行了修正计算.首先利用脉冲激光定位SRAM SEL敏感区,获得敏感区的分布情况,并确定整个器件敏感体积单元的数量.然后针对不同的空间轨道、辐射粒子以及敏感体积厚度和敏感体积单元数进行了相应的器件SEL事件率计算,并对计算结果进行了分析讨论.结果表明,重离子引起的SEL事件率随敏感体积单元数量的增大而减小;修正敏感体积单元数量对预估质子引起的SEL事件率非常必要,否则将会过高评估质子直接电离作用对SEL事件率的贡献.

SEL rate prediction for SRAM using pulsed laser sensitivity mapping

The classical approaches for single event latchup (SEL) rate prediction are based on the rectangular parallelepiped (RPP) model of only one sensitive volume. However, the experiment results of SEL sensitivity mapping of static random access memory (SRAM) show that the device has not only one sensitive volume (SV). The in-flight SEL rate of the device was corrected using the experiment results of pulsed laser SEL sensitivity mapping of SRAM K6R4016V1D.The SEL sensitivity maps of the SRAM by pulsed laser were first obtained and then the SV number of the device was calculated. The SEL rates of the device were predicted and discussed for different space orbits, radiation particles, SV thicknesses and SV number in particular. The results show that SEL rate caused by heavy ion decreases with SV number. The correction of the SV number is essential for SEL rate due to proton direct ionization; otherwise, the contribution of direct ionization of protons to SEL rate would be greatly overestimated.