High-performance field-effect transistors with semiconducting-rich single-walled carbon nanotube bundle
Abu Taher Khan, Nan Wei, Otto Salmela, Kimmo Mustonen, Yongping Liao, Aqeel Hussain, Er‐Xiong Ding, Md Gius Uddin, Hua Jiang, Yutaka Ohno, Esko I. Kauppinen
Abstract
Single-walled carbon nanotubes (SWCNTs), typically produced as bundles in floating catalyst chemical vapor deposition (FC-CVD), exhibit exceptional electronic properties, making them highly promising for high-performance electronics. This work examines the transport characteristics and electrical performance of field-effect transistors (FETs) fabricated from two high crystalline SWCNT bundle types: Small Bundle Small Diameter (SBSD) and Large Bundle Large Diameter (LBLD). SBSD and LBLD SWCNT bundles, synthesized via FC-CVD, had mean bundle diameters of 4.1 nm and 7.1 nm, and mean tube diameters of 1.4 nm and 1.9 nm, respectively. Despite electron diffraction revealing metallic fractions of 38 % for SBSD and 46.3 % for LBLD, interestingly a higher-than-expected fraction of FETs with 71.5 % for SBSD and 62 % for LBLD, demonstrated semiconducting behavior. Single SBSD SWCNT FETs achieved a mean charge carrier mobility of 2817 cm 2 V – 1 S −1 , while single LBLD SWCNT FETs reached a mean value of 5378 cm 2 V – 1 S −1 , among the highest reported. The mean mobility in single junction FETs decreased about fourfold to 737 cm 2 V −1 s −1 for SBSD and threefold to 1732 cm 2 V −1 s −1 for LBLD, compared to the single bundle FET. Both SBSD and LBLD SWCNT FETs achieved on-off ratios up to 10 8 , highlighting their potential for advanced electronic applications.