Printing h-BN Gate Dielectric for Flexible, Low-hysteresis Carbon Nanotube Thin-Film Transistors at Low Temperature
Increasing interest in printing for flexible electronics is driven by the rapid growth and maturation of the Internet of Things (IoT) and motivates the study of printable materials and printing methods [1]. While semiconducting carbon nanotubes (CNTs) have shown promise for flexible printed electronics owing to their relatively high mobility, flexibility, and amenability to low-temperature processing techniques [2], their application in low-temperature direct-write printing of electronics has been hindered by the lack of suitable printable materials for other device layers, including dielectrics and contacts. In this work, we demonstrate fully printed carbon nanotube thin-film transistors (CNT - TFTs) where the gate dielectric is made of 2-dimensional hexagonal boron nitride (h-BN) and the contacts are made of silver nanowires (AgNWs). While exhibiting high ON/OFF current ratio (\mathrm{I}-{\mathrm{ON}}/\mathrm{I}-{\mathrm{OFF}}), low hysteresis, and excellent mechanical flexibility, the CNT- TFTs can be printed from the first step to the last using a maximum process temperature of 80°C, enabling widespread compatibility with temperature-sensitive substrates.
