Fig. 1.

Space charge-limited conduction (SCLC) characteristics of 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) diodes with and without additives. a Device structure of SCLC polymer diodes used (dimensions of crossbar overlap A = 20 × 200 µm²); b simulated structure of a high-mobility amorphous polymer (adapted from ref. ¹¹); c passivation of water-induced traps in the polymer’s microstructure through the use of additives (red). Removal of additives allows water molecules (blue) to interact with polarons on the polymer backbone and disturb charge transport; d hole-only SCLC diode characteristics for the polymer DPP-BTz (thickness 220 nm). Using a solvent additive, record, field-independent SCLC mobilities of 0.2 cm²/Vs are reached. After solvent removal, performance drops by a factor of ~500 and trap-free SCLC behavior vanishes. e Power law exponent $m=\frac{\partial \mathrm{Ln}\left(I\right)}{\partial \mathrm{Ln}\left(V\right)}$ of the SCLC characteristics extracted during repeated measurements with excellent reproducibility. The chemical structure of DPP-BTz as well as the additive (residual 1,2-dichlorobenzene (DCB) solvent) is also shown