Trap-limited electron transport in disordered semiconducting polymers

Abstract

Trap-limited electron transport in disordered semiconducting polymers Mandoc, M. M.; de Boer, B.; Paasch, G.; Blom, P. W. M.

Space-charge limited surface currents between two semi-infinite planar electrodes embedded in a uniform dielectric medium

“…It is well-known that for a 1D model and assuming an exponential distribution of traps, the J ⇠ V 2 /L 3 dependence for the (dark) injection current must be replaced by a dependence J ⇠ V r+1 /L 2r+1 , where r = T t /T 0 , with T t a temperature describing the trap distribution and T 0 the ambient temperature. This behavior can be explained on the basis of a model with a small fraction of mobile carriers with fixed mobility whose density depends on the trapped density according to p ⇠ p r t [8], or considering carriers with a density dependent mobility µ ⇠ p r 1 [29,10]. The dependence can easily be found using a scaling argument as was done by Langmuir [2].…”

“…both types of carriers are injected, or because traps are present [3,7,8] or because the mobility is field dependent [9] and/or carrier density dependent [10] and so on. All formulas mentioned and possible extensions have been derived for a planar one-dimensional structure.…”

Effect of Gaussian disorder on the voltage dependence of the current density in sandwich-type devices based on organic semiconductors

“…In particular, the method can be extended straightforwardly to systems containing trap states. Such an extension may be envisaged to find practical applications to dye-doped hostguest systems in, e.g., small-molecule OLEDs and to trapcontrolled hole 29 and electron [30][31][32] transport through polymers.…”

Electron and hole transport in poly(fluorene-benzothiadiazole)

“…24 The weak temperature of the traplimited electron current could be explained by incorporating the presence of a Gaussian DOS for free electrons. 25 However, modeling of the electron currents alone is not sufficient to determine the intrinsic electron mobility as well as the total amount of trap states and their position inside the band gap. We recently demonstrated that the traps can be deactivated by addition of the n-type dopant DMC.…”