Voltage Dependence of Unipolar Excess Bulk Charge Density in Organic Insulators

  • Martin Pope
  • William Weston


The steady flow of a unipolar current through a real insulator containing bulk trapping sites and provided with an injecting contact has been divided into several regimes(1). At low voltage, there should be an ohmic regime in which bulk, thermal generation of carriers predominates. This is followed at higher voltages by a space charge limited current (SCLC) regime, during which traps are filled by the excess, injected carriers. With certain trap distributions, it is sometimes found that at a particular voltage (VTFL) the current rises much more steeply with voltage than was the case for voltages less than VTFL. This voltage is referred to as the traps filled limit (TFL) voltage and it provides a ready measure of the total trap density in the crystal. At sufficiently high voltages, the contact becomes depleted and the current tends toward saturation.


Voltage Dependence Image Force Delay Fluorescence Triplet Exciton Trap Carrier 
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Copyright information

© Plenum Press, New York 1974

Authors and Affiliations

  • Martin Pope
    • 1
  • William Weston
    • 1
  1. 1.Radiation and Solid State LaboratoryNew York UniversityNew YorkUSA

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