Highly Uniform Thin-Film Transistors Printed on Flexible Plastic Films with Morphology-Controlled Carbon Nanotube Network Channels

Abstract

Carbon nanotube (CNT) transistor arrays were fabricated on plastic films by printing. All the device elements were directly patterned by maskless printing without any additional patterning process, and minimum materials were used. During fabrication, the morphology of the CNT random network was controlled by an adsorption mechanism on the surface to be printed, which resulted in excellent and uniform electrical properties. The field-effect mobility was further improved by post-treatment to modify the morphology of the CNT network. These results are promising for realizing printed electronics integrated with CNT transistors.

Low variability with high performance in thin-film transistors of semiconducting carbon nanotubes achieved by shortening tube lengths

“…17 For the SWCNTs with a 1.3 nm diameter, the extraction of the s-SWCNT fraction was carried out based on the electric-field-induced layer formation (ELF) technique, 11 which is an electrophoresis method. Semiconducting chiralities in the used SWCNTs observed by the photoluminescence mapping measurement (Horiba Spex, Fluorolog 3-2 TRIAX) were as follows: (8,6), (8,7), (9,7), (9,8), (10,5), (10,6), (10,8), (10,9), (11,3), (11,4), (11,6), (11,7), (11,9), (12,1), (12,4), (12,5), (12,7), (12,8), (13,2), (13,3), (13,5), (13,6), (14,1), and (14,3). The purity o...…”

“…3 For the printed electronics of SWCNTs, various processes, not only the printing process itself, but also the semiconducting-ink preparation and removal of surfactants by heat and/or wet treatments, are required. 4 Among these processes, recent significant advances in the extraction techniques for the ink preparation of semiconducting SWCNTs (s-SWCNTs), such as dielectrophoresis, 5 density-gradient ultracentrifugation, 6 DNA separation, 7 and gel-based extraction 8 have improved the device performance of thin-film transistors of SWCNTs (SWCNT-TFTs). Although most of the reported extraction methods need to use ionic surfactants to disperse SWCNTs, it is well known that ionic contaminations can degrade device performance.…”

A Review of Carbon Nanotube‐ and Graphene‐Based Flexible Thin‐Film Transistors

“…Carrier doping processes to achieve complementary metal oxide semiconductor (CMOS) circuits are also compatible with liquid‐phase fabrication 139, 140. However, it is usually difficult to form a uniform film by printing,141 though H. Mumata et al reported highly uniform printed CNT thin‐film transistors produced by an adsorption mechanism 142…”

Highly stretchable carbon nanotube transistors enabled by buckled ion gel gate dielectrics

“…More reproducible casting techniques, for example, spray printing, will likely allow for better control of film thickness in future implementations. 28,29 Nonetheless, all the FETs demonstrate relatively stable performance up to 80% strain.…”