同步动态随机存储器辐射效应测试系统研制

Development of measurement system for radiation effects on synchronous dynamic random access memory

在分析同步动态随机存储器(SDRAM)辐射效应主要失效现象的基础上,研制了具备了读写功能测试、刷新周期测试及功耗电流测试三种功能的SDRAM辐射效应在线测试系统,并开展了SDRAM的总剂量效应实验研究。结果表明,总剂量效应会导致SDRAM器件的数据保持时间不断减小,功耗电流不断增大以及读写功能失效。实验样品MT48LC8M32B2的功能失效主要由外围控制电路造成,而非存储单元翻转。数据保持时间虽然随着辐照剂量的累积不断减小,但不是造成该器件功能失效的直接原因。

An online measurement system for radiation effects on synchronous dynamic random access memory （SDRAM） is developed on the basis of the analysis of the main failure phenomenon, which can test the function, refresh period and power supply current. The results of an experiment on SDRAM for total ionizing dose effect （TID） show that the TID can cause the de- crease in data retention time, the increase in power supply current and the functional failure. For the samples MT48LCSM32B2, its functional failure is caused by the peripheral control circuits, rather than the memory unit upset. Data retention time keeps de- creasing with the increase of the total dose, but this is not the directive reason for the functional failure of SDRAM.