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

A pre-irradiation elevated-temperature stress is shown to have a significan t impact on the radiation response of a linear bipolar circuit. Thermal cyc ling can lead to part-to-part variability in the radiation response of circ uits packaged from the same wafer. In addition, it is demonstrated that a p re-irradiation elevated-temperature stress can significantly impact the enh anced low dose rate sensitivity (ELDRS) of the LM111 voltage comparator. Th ermal stress moderates and, in some cases, eliminates ELDRS, The data are c onsistent 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 a ssurance testing and mechanisms are discussed.