Flexible carbon nanotube Schottky diode and its integrated circuit applications

Carbon nanotubes (CNTs), a low-dimensional material currently popular in industry and academia, are promising candidates for addressing the limits of existing semiconductors. In particular, CNTs are attractive candidates for flexible electronic materials due to their excellent flexibility and potential applications. In this work, we demonstrate a flexible CNT Schottky diode based on highly purified, preseparated, solution-processed 99% semiconducting CNTs and an integrated circuit application using the CNT Schottky diodes. Notably, the fabricated flexible CNT diode can greatly modulate the properties of the contact formed between the semiconducting CNT and the anode electrode via the control gate bias, exhibiting a high rectification ratio of up to 2.5 × 10⁵. In addition, we confirm that the electrical performance of the CNT Schottky diodes does not significantly change after a few thousand bending/releasing cycles of the flexible substrate. Finally, integrated circuit (IC) applications of logic circuits (OR and AND gates) and an analog circuit (a half-wave rectifier) were presented through the use of flexible CNT Schottky diode combinations. The correct output responses are successfully achieved from the circuit applications; hence, we expect that our findings will provide a promising basis for electronic circuit applications based on CNTs.