Improved electrical stability in cyclically bent organic thin film transistors with nanocomposite gate dielectrics and surface passivation

This paper investigates reliability improvements in cyclically bent bottom-gated pentacene organic thin film transistors by employing surface passivation as well as nanocomposite gate dielectrics. The variation in the hysteresis of the cyclically bent nanocomposite devices with increased Al2O3 nanoparticle fractions without surface passivation decreased. This was primarily attributed to the absence of change in charge trapping sites such as hydroxyl (OH) groups in the gate dielectrics due to reduced susceptibility of the nanocomposite dielectrics to penetration of water molecules. Furthermore, surface passivation of the devices by depositing organic thin films effectively improved their stability in the off-state current due to protection of the pentacene, which prevented penetration of ambient water. (C) 2009 American Institute of Physics. [doi: 10.1063/1.3224909]