Radiation Resistance of Microelectronic Systems

The radiation resistance of microcircuit systems has been studied by testing separate microcircuits and using statistics based on known data of the transistor damage coefficients. The logic gates with bipolar transistors can be characterized by a transistor base transit time, tb, defined as tb=0.2/f¿ where f¿ is the alpha cutoff frequency. When tbÿ < 105ns/cm2 the separate gates almost certainly survive, failure almost certainly occuring when tbÿ > 107ns/cm2. The quantity ÿ is the fast neutron exposure of a reactor spectrum (E > 10 keV).