Ring oscillator made of organic thin-film transistors produced by self-organized process on plastic substrate

The authors studied the fabrication of a ring oscillator consisting of organic inverters showing no hysteresis in output characteristics. They designed and fabricated the ring oscillator with bootstrapping inverters made of pentacene organic thin-film transistors on plastic produced by self-organized process, exhibiting the field-effect mobility of ∼0.6cm2∕Vs, on/off current ratio of 107, and threshold voltage of −5V. The oscillation frequency of 3kHz and signal propagation delay of 15μs per stage were achieved for an 11-stage oscillator with a supply voltage of 20V.