11:00 AM - *EP06.01.02
Understanding Tunnel Currents in Organic Transistors—From New Theoretical Models to New Devices
Bjorn Lussem1,Shiyi Liu1,Akram Al-Shadeedi1,Max Tietze2,Chang-Min Keum1,3
Kent State University1,University of Leuven2,University of St Andrews3
A thorough understanding of tunnel currents in disordered organic semiconductors is essential to understand charge transport and injection into disordered organic semiconductors1–3. Furthermore, tunnel currents provide an additional parameter space to design novel devices, e.g. organic Zener-Diodes4,5, AC-driven OLEDs6, or inversion type OFETs7,8.
In this presentation, a new analytic model to describe HOMO to LUMO tunneling in organic Zener diodes is presented. It is shown that the particular shape of the density of states in the organic layer determines the breakdown voltage in these diodes. Furthermore, the ideality factor of the diodes is shown to be limited by the width of the density of states and the roughness of the organic layer.
Based on this model, approaches to widen the design space of organic field-effect transistors are discussed. It is shown, how HOMO to LUMO tunneling can be used to facilitate ambipolar injection and generation of minority charge carriers in organic field-effect transistors7. Furthermore, the design and performance of Organic Tunnel Field-Effect Transistors is presented and ways to improve their performance are discussed.
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