Neutron Induced Damage in P- and N-Type PbS Single Crystal Films,

The Hall coefficient, resistivity, and charge carrier mobility of epitaxial films of n- and p-type PbS having carrier concentrations between 1 x 10 to the 17th powercc and 1 x 10 to the 18th powercc were measured in the temperature range of 4.5 and 300K before and after successive neutron irradiations. The irradiations in the National Bureau of Standards reactor at Gaithersburg, Maryland were in four steps of approximately 3.5 x 10 to the 16th power neutrons per sq. cm. each. The variation of the Hall coefficient with irradiation level was used to calculate the carrier removal rate. Information about radiation induced localized energy states in the energy band gap obtained from change of the Hall coefficient with temperature. The variation of mobility with temperature provided information about the defect scattering mechanism Cascade displacement theory was applied to PbS to predict the concentrations of Pb and S displacements. This information in conjunction with the carrier removal rate gave the number of removals per defect pair. Author