Thermal-stress effects and enhanced low dose rate sensitivity in linear bipolar ICs

A pre-irradiation elevated-temperature stress is shown to have a significant impact on the radiation response of a linear bipolar circuit. Thermal cycling can lead to part-to-part variability in the radiation response of circuits packaged from the same wafer. In addition, it is demonstrated that a pre-irradiation elevated-temperature stress can significantly impact the enhanced low dose rate sensitivity (ELDRS) of the LM111 voltage comparator. Thermal stress moderates and, in some cases, eliminates ELDRS. The data are consistent with space charge models. These results suggest that there may be a connection between the mechanisms responsible for thermal-stress effects and ELDRS in linear circuits. Implications of these results for hardness assurance testing and mechanisms are discussed.