Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)


Department of Engineering Physics

First Advisor

James C. Petrosky, PhD.


As legacy neutron irradiation facilities are shut down due to security and financial constrictions, a growing need arises for alternatives that can provide the same or similar radiation environments using methods and/or fuels that do not pose the same risks. For this reason, facilities that provide much lower neutron fluxes and different spectral shapes are being leveraged over longer irradiation intervals to meet this need. However, the question arises as to whether the use of these types of facilities provide a valid comparison to the legacy systems' results. To this end, a model using a system of coupled, non-linear ordinary differential equations has been developed to track defect species in silicon for short pulse neutron irradiations. This model has been used to predict current gain degradation in silicon BJTs for various neutron influences. These predictions have been compared against experimental data collected at two neutron irradiation facilities with different time and spectral profiles. The damage constant during irradiation has been determined, and it is different for both facilities. However, the time profile is found to have no effect in the region tested in this work. Now that this analysis has been done, these types of facilities can be used for radiation vulnerability analysis studies for use in short pulse neutron damage studies.

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