Temperature Dependence of Radiation Induced Conductivity in Insulators

Authors

John R. Dennison, Utah State UniversityFollow
Jodie Gillespie
Joshua Hodges
RC Hoffman
J. Abbott
Alan W. Hunt
Randy Spalding

Document Type

Article

Journal/Book Title/Conference

American Institute of Physics Conference Proceedings Series

Volume

1099

Publisher

American Institute of Physics

Publication Date

3-10-2009

First Page

203

Last Page

208

Abstract

Thisstudy measures Radiation Induced Conductivity (RIC) of Low Density Polyethylene(LDPE) over temperatures ranging from ~110 K to ~350 K. RIC occurswhen incident ionizing radiation deposits energy and excites electrons intothe conduction band of insulators. Conductivity was measured when avoltage was applied across vacuum-baked, thin film LDPE polymer samplesin a parallel plate geometry. RIC was calculated as thedifference in sample conductivity under no incident radiation and underan incident ~4 MeV electron beam at low incident fluxes of10⁻⁴–10⁻¹ Gr/sec. The steady-state RIC was found to agree well withthe standard power law relation, _RIC = k_RIC· between conductivity, andadsorbed dose rate, . Both the proportionality constant, k_RIC, andthe power, , were found to be temperature dependant above~250 K, with behavior consistent with photoconductivity models developed for localizedtrap states in disordered semiconductors. Below ~250 K, kRIC and exhibited little change. The observed difference in temperature dependence mightbe related to a structural phase transition seen at T~256 Kin prior studies of mechanical and thermodynamic properties of LDPE. ©2009 American Institute of Physics

Comments

Published by the American Institute of Physics in American Institute of Physics: Conference Proceedings Series. Publisher PDF is available for download through the link above.

Recommended Citation

JR Dennison, Jodie Gillespie, Joshua Hodges, RC Hoffmann, J Abbott, Alan W. Hunt and Randy Spalding, “RadiationInduced Conductivity of Highly-Insulating Spacecraft Materials,” in Application of Accelerators in Research andIndustry, American Institute of Physics Conference Proceedings Series, Vol. 1099, ed. Floyd D. McDaniel and Barney L.Doyle,(American Institute of Physics, Melveille, NY, 2009), pp. 203-208