基于硅胶快速吸附的碳纳米管长度分选及其晶体管性能研究

Research on Length-Sorted of Carbon Nanotubes Based on Silica Gel Rapid Adsorption and Transistor Performance

摘要:

半导体型单壁碳纳米管是下一代场效应晶体管及集成电路中最具有应用前景的沟道材料之一。半导体型单壁碳纳米管在分散与分离过程中长度会被截短。大量长度100 nm以下的超短管的存在会增加管间搭接电阻和增加载流子的散射几率,从而导致器件性能的下降,不利于高性能碳纳米管器件的发展和应用。但尚缺乏在有机体系中对半导体型碳管长度分选,特别是超短管可控去除的研究。本文中,我们发展了一种有机体系的硅胶吸附技术,成功实现了超短碳管的高效去除,使半导体型碳纳米管的长度分布实现了有效调控。基于长度分选后的碳纳米管制备的晶体管器件,其开态电流和最大跨导达到8.9 μA/μm和0.5 mS/μm,比长度未分选的器件性能分别提高了约300%和250%。

Abstract:

Semiconductor single walled carbon nanotubes (s-SWCNTs) is one of the most promising channel materials for the next generation of field effect transistors and integrated circuits. The length of s-SWCNTs is shortened during dispersion and separation. The existence of many ultra-short tubes with length less than 100 nm will increase the lap resistance between tubes and increase the scattering probability of carriers, which will lead to the degradation of device performance. It is not beneficial to the development and application of high-performance carbon nanotube devices. However, there is still a lack of research on the separation of s-SWCNTs length in organic system, especially the controllable removal of ultra-short tubes. In this paper, we developed a silica gel adsorption technology in organic system, which successfully achieved the efficient removal of ultra-short carbon nanotubes and effectively regulated the length distribution of semiconductor carbon nanotubes. The on-state current and maximum transconductance of the transistors prepared by the CNTs with length-sorted are 8.9 μA/μm and 0.5 mS/μm, which are about 300% and 250% higher than those of the device without length-sorted, respectively.