Optimization of single-walled carbon nanotube growth and study of the hysteresis of random network carbon nanotube thin film transistors

Random network single-walled carbon nanotube (SWNT)-based thin film transistors show excellent properties in sensors, electronic circuits, and flexible devices. However, they exhibit a significant amount of hysteresis behavior, which should be solved prior to use in industrial applications. This paper provides optimum conditions for the growth of random network SWNTs and reveals that the observed hysteresis behavior originates from the charge exchange between the SWNTs and the dielectric layer rather than from changes in the intrinsic properties of the SWNTs. This was proven by studying the conditions of stepwise gate sweep experiments and time measurements. This paper also shows that top gate SWNT thin film transistors (TFTs) with an SU-8 dielectric layer could provide a practical solution to the hysteresis problem for SWNT TFTs in electronic circuit applications.