EEPROM 28C64和28C256的14MeV中子辐照特性

Characteristics of EEPROM 28C64 and 28C256 by 14 MeV Neutron Radiation

给出了 Ｅ Ｅ Ｐ Ｒ Ｏ Ｍ 器件的中子辐照实验结果，发现 ２８ Ｃ６４ 和 ２８ Ｃ２５６ 的 １４ Ｍ ｅ Ｖ 中子辐照效应不是以往所认为的单粒子效应，而是总剂量效应。器件出现的错误不是随机的，而是存在中子注量阈值；不同的错误有不同的阈值。在相同的中子注量下，加电的器件出现错误，而不加电的器件无错误；对于 ２８ Ｃ２５６，“０”→“１”错误比“１”→“０”错误容易发生；存贮单元由一种状态彻底变为相反状态之前的一段时间内，其状态是不确定的；停止辐照后，中子注量不再增加时，错误数仍在增加，说明是控制部件出错导致的。

Experimental results of neutron irradiation effects on EEPROM devices are presented. Effects in EEPROM 28C64 and 28C256 by 14 MeV neutron irradiation are total dose effects rather than single event effects. Errors do not occur randomly. Moreover, there are neutron flux thresholds. The thresholds are different for different errors. For the same neutron flux, there is no error in devices in power off mode, however, errors occur in all devices in power on mode. For 28C256, it is found that “0”→“1” error is more likely to occur than “1”→“0” error; that the state of the memory cell is undefined before it thoroughly changes into its opposition; and the data errors still increase after irradiation, implying that something must have been wrong with control parts.