Results of a combined experimental and modeling study of electron transport in a blue-emitting polyfluorene-based copolymer in sandwich-type devices are presented. We show how, for wide temperature and layer thickness ranges, an accurate and internally consistent drift-diffusion model description of the voltage-dependent current density can be obtained. We employ an adapted form of the "extended Gaussian disorder model," within which the density of states (DOS) is described as a superposition of a Gaussian DOS and an exponential DOS ("trap states"), characterized by only a small set of physically meaningful parameters. A comparison is made with the hole mobility reported for related polymers.
Mensfoort, van, S. L. M., Billen, J. G. J. E., Vulto, S. I. E., Janssen, R. A. J., & Coehoorn, R. (2009). Electron transport in polyfluorene-based sandwich-type devices: Quantitative analysis of the effects of disorder and electron traps. Physical Review B, 80(3), 033202-1/4. . https://doi.org/10.1103/PhysRevB.80.033202