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

Abstract

In this study, the semiconducting single-walled carbon nanotube (semi-SWCNT) thin film transistors (TFTs) with high dielectric constant (κ) atomic layer deposited ZrAlOx 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 ZrAlOx 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 ZrAlOx 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.