为了研究大规模集成电路存储器的总剂量辐射效应,分别对SRAM和ROM两种存储器进行了60Co γ总剂量辐射实验。结果表明,这两种器件是对总剂量辐射效应敏感的器件,失效阈值在10~15 krad(Si)之间。实验还表明,研究SRAM、ROM的总剂量辐射效应,只对数据存取功能进行测试是不完善的,器件的静态功耗电流与动态功耗电流也是总剂量辐射效应的敏感参数,应该作为总剂量辐射效应失效阈值的有效判据。根据器件结构与实验结果,分析了SRAM和ROM器件的损伤机理,认为CMOS SRAM的损伤主要源于辐射产生的界面效应;而浮栅结构ROM的损伤则源于辐射产生的氧化物陷阱电荷与界面陷阱电荷。

In order to research the Total Dose Effects (TDEs) of the storages for Very Large Scale Integrated circuits(VLSIs),two kinds of devices,SRAM and ROM, are used as samples in a radiation experiment,and a60Co γ source is selected as the radiation source.Experiments indicates that both devices are sensitive to the TDEs,and their damage thresholds are 10~15 krad(Si).Experiments also suggest that research on the TDEs of SRAM and ROM should take the static consumption current and dynamic consumption current as the effective criterions for the damage threshold of TDEs other than testing the data access function only,because the static consumption current and dynamic consumption current are all sensitive to TDEs.On the foundation of analysing the device structure and experiment results,the damage reasons of TDEs are analyzed,and results show that the damage of CMOS SRAM is from the interface effect caused by TDEs and the damage of floating gate ROM is from the oxide charges and interface trapped charges caused by TDEs.