Performance Enhancement of Carbon Nanotube Network Transistors via SbI₃ Inner-Doping in Selected Regions

Semiconducting single-wall carbon nanotubes (s-SWCNTs) represent one of the most promising materials for surpassing Moore's Law and developing the next generation of electronic devices. Despite numerous developed approaches, reducing the contact resistance of s-SWCNTs networks remains a significant challenge in achieving further enhancements in electronic performance. In this study, antimony triiodide (SbI₃) is efficiently encapsulated within high-purity s-SWCNTs films at low temperatures, forming 1D SbI₃@s-SWCNTs vdW heterostructures. The semiconductor-metal transition of individual SbI₃@s-SWCNTs is characterized via sensitive dielectric force microscopy, with the results confirmed through electrical device tests. The electrical behavior transition is attributed to an interlayer charge transfer, as demonstrated by Kelvin probe force microscopy. Moreover, the electrical performance of s-SWCNTs thin-film transistors improves significantly with SbI₃@s-SWCNTs networks as contact electrodes. This process reduces the contact resistance between the s-SWCNTs channel and the electrodes, enhancing electrical performance. Specifically, the contact resistance decreases to one-third of the original, the carrier mobility increases by ≈10 times, the on-off ratio exceeds 10⁶, and the subthreshold swing reduces significantly to ≈65 mV dec^-1. These results demonstrate the effectiveness of inner-doping-induced metallization of s-SWCNTs in the contact region, essential for advancing carbon nanotube electronic devices and circuits.