Parts | Days | Selection | Search | Updates | Downloads | Help
HL: Fachverband Halbleiterphysik
HL 14: 2D Materials III (joint session HL/CPP)
HL 14.6: Talk
Tuesday, March 28, 2023, 11:00–11:15, POT 81
high responsivity monolayer MoS2 photodetectors on cyclic olefin copolymer-passivated SiO2 gate dielectric — •Emad Najafidehaghani1, Sirri Batuhan Kalkan2, Ziyang Gan1, Jan Drewniok2, Michael F Lichtenegger2, Uwe Hübner3, Alexander S Urban2, Antony George1, Bert Nickel2, and Andrey Turchanin1 — 1Friedrich Schiller University Jena, Institute of Physical Chemistry, Jena — 2Ludwig Maximilian University of Munich, Faculty of Physics, Munich — 3Leibniz Institute of Photonic Technology (IPHT), Jena
2D material-based photodetectors attracted significant research interest due to their high responsivity, flexibility and transparency. However, the trap states present at the surface of SiO2 gate dielectrics diminishes the performance of 2D material-based photodetectors. To reduce the detrimental effect of SiO2 surface traps, an ultrathin film (5 nm) of cyclic olefin copolymer (COC) layer is employed as a surface passivator. Due to the reduction of the interface trap density, the photoresponsivity of the MoS2 devices on passivated SiO2 is enhanced by four orders of magnitude compared to non-passivated MoS2 devices. Under optimized conditions a record photoresponsivity of 3× 107 A/W in combination with a short response time is observed. Our findings show that the ultrathin COC passivation of the gate dielectric enables to probe exciting properties of the atomically thin 2D semiconductors.