Complementary circuit with self-alignment organic/oxide thin-film transistors

Complementary logic circuits with self-alignment organic/oxide thin-film transistors (TFTs) were investigated. The layout and process steps of a self-alignment bottom-contact-type organic TFT and a top-contact type oxide TFT with a common layout pattern of the gate, source, and drain electrodes were proposed, and an integrated circuit was realized. The estimated field-effect mobilities, threshold voltages, and on-off ratios of the organic and oxide TFTs were 0.16 and 2.2 cm ² V ^-1 s ^-1, 2.2 and 2 V, and 3 × 10 ³ and 5.2 × 10 ⁶, respectively. From the complementary inverter characteristics, the voltage gain was 13 and the logic swing was 9.8V at an applied voltage of 10 V. From the switching characteristics of the inverter, the rise and fall times were 18 and 46 μs, respectively. The operations of the NAND and NOR logic circuit configurations were confirmed, and the maximum operational frequency of NAND logic was estimated to be over 100 kHz.