Proceedings of the 13th Spacecraft Charging Technology Conference
Expressions are developed for radiation induce conductivity (RIC) over an extended temperature range, based on density of states models for highly disordered insulating materials. A general discussion of the DOS of can be given using two simple types of DOS distributions of defect states within the bandgap for disordered materials are considered, one that monotonically decreases within the bandgap and one with a distribution peak within the band gap. Three monotonically decreasing models (exponential, power law, and linear), and two peaked models (Gaussian and delta function) are considered, plus limiting cases with a uniform DOS for each type. Variations using the peaked models are considered, with an effective Fermi level between the conduction mobility edge and the trap DOS, within the peaked trap DOS, and between the trap DOS and the valence band. The models are compared to measured RIC values over broad temperature ranges for two common materials, low density polyethylene (LDPE) and disordered silicon dioxide.
Jodie Corbridge Gillespie, JR Dennison and Alec M. Sim, “Density of State Models and Temperature Dependence of Radiation Induced Conductivity,” Abstract 113, Proceedings of the 13th Spacecraft Charging Technology Conference, (Pasadena, CA, June 25-29, 2014), 8 pp.