The I-V characteristics of organic hole-only devices based on crosslinked hole-transport layer

Commonly, organic electronics devices are build up from the organic semiconductor thin films which are prepared either by thermal vacuum evaporation or by solution-processing techniques such as spin casting, inkjet printing, or roll-to-roll printing. The solution-processing has several advantages although it has a crucial problem for multilayer device preparation where the first layer will be dissolved by the solvent of the second layer. The using of insoluble layer is a solution of this problem. This paper reports the electrical (I-V) characteristics of Hole-Only Devices (HOD) which are prepared via solution processing by using insoluble layer. The insoluble layer based on triphenylamine dimmer was sandwiched in the two electrodes as anode and cathode. This insoluble layer was prepared via oxetane ring-opening polymerisation either oxidative crosslinking, photo crosslinking, or trityl crosslinking. The measurement was carried out to get current density versus electric-field strength characteristic as a function of oxidation potential, polymerisation mechanism, the amount of oxidant, and curing temperature. The measurement confirmed that the crosslinked hole-transport layers are successfully applied in HOD, the oxidative crosslinking mechanism showed the doping effect, and the amount of oxidant influences the conductivity of crosslinked layer.