title: Organic homojunction diodes with a high built-in potential: interpretation of the current-voltage characteristics by a generalized Einstein relation.
abstract: We realize p- and n-type doping of the organic semiconductor zinc-phthalocyanine using a novel strong organic donor. This allows us to demonstrate the first stable and reproducible organic p-n homojunctions. The diodes show very high built-in potentials, attractive, e.g., for organic solar cells. However, the diode characteristics cannot be described by the standard Shockley theory of the p-n junction since the ideality factor strongly increases with decreasing temperature. We show that this behavior can be explained by deviations from the Einstein relation for disordered materials.
authors.affiliation: Institut für Angewandte Photophysik, Technische Universität Dresden, 01062 Dresden, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Harada
authors.forename: A G
authors.initials: AG
authors.lastname: Werner
authors.forename: M
authors.initials: M
authors.lastname: Pfeiffer
authors.forename: C J
authors.initials: CJ
authors.lastname: Bloom
authors.forename: C M
authors.initials: CM
authors.lastname: Elliott
authors.forename: K
authors.initials: K
authors.lastname: Leo