Effect of active layer thickness on bias stress effect in pentacene thin-film transistors

The bias stress effect in pentacene thin-film transistors is characterized for different active layer thicknesses. We show that the shift in threshold voltage under applied bias is accelerated as the pentacene semiconductor layer thickness is increased from 10 to 80 nm, and that this trend is not correlated with current, initial threshold voltage, or turn-on voltage. This study sheds light on the role of active material above the conductive channel in thin-film devices and describes effects that are important to consider when optimizing the structure of organic thin-film transistors. (c) 2006 American Institute of Physics.