Fig. 2.

Density of trap states in poly[[2,5-bis(2-octadecyl)-2,3,5,6-tetrahydro-−3,6-diketopyrrolo[3,4-c]pyrrole-1,4-diyl]-alt-(2-octylnonyl)-2,1,3-benzotriazole] (DPP-BTz) space charge-limited conduction (SCLC) diodes. a Log–Log J–V characteristics of a DPP-BTz diode (d = 220 nm) with a solvent additive (1,2-dichlorobenzene (DCB)) measured at temperatures between 300 and 160 K; each characteristics was recorded three times to exclude degradation. b Corresponding power law exponent, $m=\frac{\partial \mathrm{Ln}\left(I\right)}{\partial \mathrm{Ln}\left(V\right)}$, of the SCLC characteristics as a function of temperature. The colors of the individual curves correspond to those in a. The width of the trap distribution (E_B) is estimated from Eq. 2 from the extended plateau (2 V) and is shown as an inset for all temperatures. c Arrhenius-type temperature activation of the current density for voltages between 0.5 and 5 V. d dn/dE values extracted for DPP-BTz devices with and without an additive. The dn/dE is shown for two separate devices (device A with a thickness of 170 nm and device B with a thickness of 220 nm), with the additive removed by annealing (blue) or by extended storage in vacuum (red)