Displacement Damage in Silicon Irradiated with 6-to 10-MeV Neutrons.

摘要

Some preliminary experimental and theoretical results on the energy dependence of neutron-induced displacement damage in silicon are presented. The reduction in carrier lifetime, as reflected in the change in forward voltage at a fixed injection level, has been measured in wide-base silicon diodes, for monoenergetic neutrons at selected energies between 5.6 and 9.8 MeV. Twenty-five measurements at 19 energies were made. To calculate the variations in damage with neutron energy, a computer program that could utilize all details of the best available neutron cross section data was prepared. This program accepts coefficients for a Legendre polynomial fit of a partial cross section, determines the silicon recoil energy at a particular angle, and calculates the Lindhard fraction of energy for displacement damage. The calculated results provide a direct indication of the effect of angular distributions and the sensitivity of damage calculations to various details of the input neutron cross sections. (Author)