Investigation of Transport Phenomena in Thin Oligothiophene Films in Metal/Organic/Metal Hetero-Structures

Abstract
Electrical transport properties of thin films of evaporated end-capped oligothiophene were studied by current/voltage measurements between gold microcontacts. The experiments were performed as a function of dimension of the microstructures, film thickness, chain length of the oligomers, doping state and time. The devices show ohmic behavior and a clear dependence of the conductivities on the inverse chain length. Strong dependence of the conductivities on doping time is observed for different electrode distances. The results are compared with doping experiments on macroscopic thin films.