Neutron hardness assurance techniques for ttl integrated circuits

Correlation and screening techniques for neutron degradation of TTL integrated circuits have been examined at three different levels: measurements restricted to normal electrical leads, measurements using special internal leads, and measurements with a special chip level breakout transistor. The results of this study show much higher prediction accuracies for neutron degradation when the special lead or breakout transistor measurements are used. The special lead approach can be implemented with DC measurements, and it is feasible to make these measurements at the wafer probe level to eliminate the necessity of changing the pinout on the packaged device. These special leads can be added to radiation-hardened circuits to optimize their application to high reliability systems.