title: Influence of chemically p-type doped active organic semiconductor on the film thickness versus performance trend in cyanine/C60bilayer solar cells.
abstract: Simple bilayer organic solar cells rely on very thin coated films that allow for effective light absorption and charge carrier transport away from the heterojunction at the same time. However, thin films are difficult to coat on rough substrates or over large areas, resulting in adverse shorting and low device fabrication yield. Chemical p-type doping of organic semiconductors can reduce Ohmic losses in thicker transport layers through increased conductivity. By using a Co(III) complex as chemical dopant, we studied doped cyanine dye/C60bilayer solar cell performance for increasing dye film thickness. For films thicker than 50 nm, doping increased the power conversion efficiency by more than 30%. At the same time, the yield of working cells increased to 80%. We addressed the fate of the doped cyanine dye, and found no influence of doping on solar cell long term stability.
authors.affiliation: Empa, Swiss Federal Institute for Materials Science and Technology, Laboratory for Functional Polymers, CH-8600 Dübendorf, Switzerland; Institut des Matériaux, Ecole Polytechnique Fédérale de Lausanne, EPFL, Station 12, CH-1015 Lausanne, Switzerland.
authors.forename: Sandra
authors.initials: S
authors.lastname: Jenatsch
authors.affiliation: Empa, Swiss Federal Institute for Materials Science and Technology, Laboratory for Functional Polymers, CH-8600 Dübendorf, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Geiger
authors.affiliation: Empa, Swiss Federal Institute for Materials Science and Technology, Laboratory for Functional Polymers, CH-8600 Dübendorf, Switzerland.
authors.forename: Jakob
authors.initials: J
authors.lastname: Heier
authors.affiliation: Zürich University of Applied Sciences, Institute of Computational Physics, Technikumstrasse 9, CH-8401 Winterthur, Switzerland.
authors.forename: Christoph
authors.initials: C
authors.lastname: Kirsch
authors.affiliation: Empa, Swiss Federal Institute for Materials Science and Technology, Laboratory for Functional Polymers, CH-8600 Dübendorf, Switzerland; Institut des Matériaux, Ecole Polytechnique Fédérale de Lausanne, EPFL, Station 12, CH-1015 Lausanne, Switzerland.
authors.forename: Frank
authors.initials: F
authors.lastname: Nüesch
authors.affiliation: Empa, Swiss Federal Institute for Materials Science and Technology, Laboratory for Functional Polymers, CH-8600 Dübendorf, Switzerland.
authors.forename: Adriana
authors.initials: A
authors.lastname: Paracchino
authors.affiliation: Empa, Swiss Federal Institute for Materials Science and Technology, Laboratory for Functional Polymers, CH-8600 Dübendorf, Switzerland.
authors.forename: Daniel
authors.initials: D
authors.lastname: Rentsch
authors.affiliation: Zürich University of Applied Sciences, Institute of Computational Physics, Technikumstrasse 9, CH-8401 Winterthur, Switzerland.
authors.forename: Beat
authors.initials: B
authors.lastname: Ruhstaller
authors.affiliation: Empa, Swiss Federal Institute for Materials Science and Technology, Laboratory for Functional Polymers, CH-8600 Dübendorf, Switzerland.
authors.forename: Anna
authors.initials: A
authors.lastname: C Véron
authors.affiliation: Empa, Swiss Federal Institute for Materials Science and Technology, Laboratory for Functional Polymers, CH-8600 Dübendorf, Switzerland.
authors.forename: Roland
authors.initials: R
authors.lastname: Hany
keywords: bilayer; cyanine dye; doping; organic solar cell