All Physics Faculty Publications

Document Type

Article

Journal/Book Title/Conference

American Institute of Physics Conference Proceedings Series

Volume

1099

Editor

Floyd D. McDaniel, Barney L. Doyle

Publisher

American Institute of Physics

Publication Date

3-10-2009

First Page

203

Last Page

208

DOI

10.1063/1.3120015

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 = kRIC· between conductivity, andadsorbed dose rate, . Both the proportionality constant, kRIC, 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.