Fast organic electronic circuits based on ambipolar pentacene field-effect transistors

Inverter circuits and ring oscillators have been prepared based on the organic semiconductor pentacene. High-purity pentacene single crystals and thin films exhibit ambipolar transport properties, i.e., n- and p-channel transistor activity. This feature is very attractive for complementary logic electronic circuits, since only one organic material has to be used. Switching frequencies up to 11 MHz have been achieved for single crystal circuits. Thin film devices prepared on flexible polyimide substrates revealed delays of 0.1 μs per stage resulting in oscillation frequencies up to 900 kHz. At the request of the authors and editor, this article is being retracted effective 24 February 2003.