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Evidence of Water-related Discrete Trap State Formation in Pentacene Single Crystal Field-Effect Transistors

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 نشر من قبل Claudia Goldmann
 تاريخ النشر 2005
  مجال البحث فيزياء
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We report on the generation of a discrete trap state during negative gate bias stress in pentacene single crystal flip-crystal field-effect transistors with a SiO2 gate dielectric. Trap densities of up to 2*10^12 cm^-2 were created in the experiments. Trap formation and trap relaxation are distinctly different above and below ~280 K. In devices in which a self-assembled monolayer on top of the SiO2 provides a hydrophobic insulator surface we do not observe trap formation. These results indicate the microscopic cause of the trap state to be water adsorbed on the SiO2 surface.



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