Optical-reconfigurable carbon nanotube and indium-tin-oxide complementary thin-film transistor logic gates†
Abstract
Optically transparent thin-film transistors (TFTs) have recently attracted significant attention for a new generation of transparent electronics where p- and n-channel transistors form the basic building block for complementary analog and digital integrated circuits (ICs). This paper reports a hybrid integration of p-channel carbon nanotube (CNT) and n-channel junctionless indium-tin-oxide (ITO) TFTs using a simple and cost-effective shadow mask-assisted fabrication process. The fabricated devices exhibit a high transmittance of ∼90% in the visible light region and function as inverters, NAND and NOR gates. More interestingly, distinct optoelectronic responses of the CNT- and ITO-TFTs to ultraviolet light have been clearly observed. In addition to conventional electrically gated logic operations, simple optical-reconfigurable logic operations have been realized with hybrid CNT/ITO-TFT based logic gates. The results suggest that introducing optical-modulation to the logic gates could increase the functionalities compared with the traditional electrically driven counterparts.