Recent Progress in Obtaining Semiconducting Single-Walled Carbon Nanotubes for Transistor Applications

• Published in: Advanced materials (Weinheim) Vol. 27; no. 48; pp. 7908 - 7937
• Main Authors: Islam, Ahmad E., Rogers, John A., Alam, Muhammad A.
• Format: Journal Article
• Language: English
• Published: Germany Blackwell Publishing Ltd 22.12.2015
• Subjects: carbon nanotubes; Collection; field-effect mobility; Integrated circuits; Integrity; on/off ratios; on/off ratios, semiconducting purity; Purity; semiconducting purity; Semiconductor devices; Single wall carbon nanotubes; transistor applications; Transistors; Utilities; on/off ratios, semiconducting purity; field-effect mobility; carbon nanotubes; transistor applications
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.201502918

High purity semiconducting single‐walled carbon nanotubes (s‐SWCNTs) with a narrow diameter distribution are required for high‐performance transistors. Achieving this goal is extremely challenging because the as‐grown material contains mixtures of s‐SWCNTs and metallic‐ (m‐) SWCNTs with wide diameter distributions, typically inadequate for integrated circuits. Since 2000, numerous ex situ methods have been proposed to improve the purity of the s‐SWCNTs. The majority of these techniques fail to maintain the quality and integrity of the s‐SWCNTs with a few notable exceptions. Here, the progress in realizing high purity s‐SWCNTs in as‐grown and post‐processed materials is highlighted. A comparison of transistor parameters (such as on/off ratio and field‐effect mobility) obtained from test structures establishes the effectiveness of various methods and suggests opportunities for future improvements. Advances in realizing high‐purity semiconducting single‐walled carbon nanotubes via in situ and ex situ approaches are reviewed. The utility of these techniques are compared with an emphasis on materials growth approaches and operational properties of transistors to assess the quality and purity of the resulting collections of nanotubes.