Performance Enhancement of Thin-Film Transistors by Using High-Purity Semiconducting Single-Wall Carbon Nanotubes

Thin-film transistors (TFTs) using a random network of semiconductor-enriched single-wall carbon nanotubes (SWCNTs) were fabricated on a SiO2/Si substrate. Semiconductor-enriched SWCNTs were extracted from a pristine sample by centrifugation using agarose gel. Prior to depositing the SWCNTs, the substrate surface was modified by self-assembly of a monolayer of aminosilanes to produce an ideal two-dimensional network structure. As a result, all the TFTs fabricated on the substrate had on/off current ratios higher than 10(4) without electrical breakdown, while TFTs fabricated using pristine SWCNTs had a broad distribution of on/off ratios from 10(1) to 10(4). This improvement in transfer characteristics demonstrates a major advantage of using semiconductor-enriched SWCNTs. (C) 2009 The Japan Society of Applied Physics