Removing Conjugated Polymers from Aligned Carbon Nanotube Arrays

Aligned carbon nanotube (A-CNT) with high semiconducting purity and high-density have been considered as one of the most promising active channels for field-effect transistors (FETs), but conjugated polymer dispersant residues on the surface of A-CNT have become the main obstacle for its further development in electronics applications. In this work, a series of removable conjugated polymers (CPs) are designed and synthesized to achieve favorable purification and alignment for CNT arrays with a high density of approximate to 360 CNTs/mu m. Furthermore, a removal process of CPs on the CNT array film is developed. Raman spectra show that the CNTs in array film are almost not damaged after the removal process, and the G/D ratio is as high as 35. The field-effect transistors (FETs) are fabricated with a saturation current density up to 600 mu A mu m-1 and a current on-off ratio of approximate to 105, even with a relatively long channel length of approximate to 3 mu m. An efficient method has been developed to remove conjugated polymers from carbon nanotube array films. First, most of the polymers are degraded in an inert atmosphere at high temperature, and then the residual substances after annealing are rinsed on a wet cleaning platform to obtain a clean CNT array film. image