Fast Neutron Bombardment of Germanium and Silicon Esaki Diodes

Abstract

The fast neutron irradiation behavior of germanium and siliconEsaki diodes has been experimentally examined. The dominant change produced is an increase in the ``excess'' current which is proportional to integrated neutron flux. The observed increase in the vicinity of the current minimum is approximately 2.6×10−15 amp/fast neutron and 1.1×10−14 amp/fast neutron for germanium and silicon diodes respectively. Substantial changes result in the voltage‐current characteristics of the diodes employed in the decade of exposure between 1016–1017 fast neutrons/cm2 for germanium diodes and between 1015–1016 fast neutrons/cm2 for silicon diodes. One kilomegacycle cavity oscillators employing germanium diodes exhibit a marked reduction in power output in the decade of exposure between 1016–1017 fast neutrons/cm2. The magnitude of the decrease is in approximate agreement with the observed bombardment reduction of diode negative conductance.