Analyses of electrical properties and stability of organic complementary transistors

Organic complementary inverters were fabricated by integrating organic p - and n -channel thin film transistors. Bottom-gate and top-contact organic thin film transistors (OTFTs) with polyimide (PI)-modified silicon oxide dielectrics and silver electrodes exhibit similar carrier mobilities, threshold voltages, drain currents, and hysteresis. A gate-bias stress test was performed on both p- and n-type OTFTs. The threshold voltages and hysteresis decreased according to the space charge separation in the PI layer which could be explained by a space charge model. The complementary inverters based on these organic transistors exhibit high noise margins (NMs), a transfer voltage located at V_DD /2, and a gain of 40 with supply voltage VDD of +50 V. The electrical stability of the inverters measured during gate-bias stress reveals that the variations in the NMs and transition voltage remained below 5%.