Electron and hole transport in poly(p-phenylene vinylene) devices

The transport properties of electrons and holes in poly(dialkoxy-p-phenylene vinylene) (PPV) are investigated by current–voltage measurements using Ca as an electron and indium-tin-oxide as a hole injecting contact. Both the electron and hole currents are dominated by the bulk conduction properties of the PPV, in contrast to previous reports. The hole current is governed by bulk space-charge limited conductivity and a hole mobility of 0.5×10−6 cm2/V s is determined. The electron current is strongly reduced by the presence of traps with a total density of 1018 cm−3.