Arne Hoppe

• To achieve high performance organic field effect transistors (OFETs) with enhanced currents, high switching speeds and improved integration density the channel length L of the transistors is downscaled to the sub-micrometer regime. The influence of the semiconductor thickness on the electrical performance, especially on the charge carrier mobility [Mu], is analyzed. High-mobility oligo- and polythiophenes are used as semiconductor, which combine the advantages of highly ordered growth with processibility from solution. To test for better device properties in these bottom contact devices, the conjugation length of the organic semiconductor is varied. Special focus hereby lies on the contact resistance of the transistors. Devices with optimized parameters exhibit high switching frequencies beyond 2 MHz. At the time of publication, these are the fastest polymer OFETs reported in literature.