Thermal Neutron Damage in Bipolar PNP Transistors

An experimental test was made of the hypothesis that the source of anomalously large thermal neutron damage in bipolar PNP transistors is silicon bulk displacement caused by recoiling lithium atoms and alpha particles generated in the emitter as a result of the exoergic reaction: {B10(n,¿)Li7}. The data provided conclusive proof of this hypothesis, and was consistent with a theoretical equation that was developed to permit the calculation of the relative sensitivity of any given transistor to thermal neutron displacement damage.