Realization of solution-processed semiconducting single-walled carbon nanotubes thin film transistors with atomic layer deposited ZrAIO_x gate insulator

摘要

In this study, the semiconducting single-walled carbon nanotube (semi-SWCNT) thin film transistors (TFTs) with high dielectric constant (k) atomic layer deposited ZrAlO_x gate insulator are fabricated by the drop-casted method. The hysteresis characteristic, negative gate voltage stress stability, and thermal stability are studied, and the semi-SWCNT TFTs with ZrAlO_x gate insulators show a small hysteresis of 0.2 V, a little threshold voltage shift of 2.5 V under the negative gate voltage stress, and a threshold voltage shift of 2 V under the thermal stress. Such advantages are due to the amorphous structure and smooth surface of the atomic layer deposited ZrAlO_x gate insulator, which induces less trap states. In addition, the thermal stress stability of semi-SWCNT TFTs is investigated. It is found that the behavior of semi-SWCNT TFTs under thermal stress obeys the thermally activated hopping model obviously. This model explains the threshold voltage shift of the device under thermal stress, which is very reasonable.