EPROM Erasure in Transient and Total Dose Gamma Environments

Four versions of 32K bit EPROMs from three manufacturers were exposed to transient gamma and total dose radiation environments. At a maximum tested transient level of 3.9×109 rad(Si)/sec, the devices were found to be resistant to erasure. Failures from the total dose exposures occurred at different levels for the four device types. The most susceptible part type failed between 3200 and 4500 rad(Si). The most resistant type failed between 9500 and 11000 rad(Si). These variations in total dose failure threshold are attributed to the floating gate oxide thickness differences between the four versions of this EPROM.