New way to know an old friend: New method reveals clean carbon nanotube transistors with superb properties
Single-wall carbon nanotubes (SWCNT) have found many uses in electronics and new touch screen devices. Carbon nanotubes are sheets of one atom-thick layer of graphene rolled up seamlessly into different sizes and shapes. To be able to use them in commercial products like transparent transistors for phone screens, researchers need to be able to easily test nanotubes for their materials properties, and the new method helps with this.
Professor Esko I. Kauppinen’s group at Aalto has years of experience in making carbon nanotubes for electronic applications. The team’s unique method uses aerosols of metal catalysts and gasses containing carbon. This aerosol-based method allows the researchers to carefully control the nanotube structure directly.
Fabricating single carbon nanotube transistors is usually tedious. It often takes days from raw carbon nanotube material to transistors, and the devices were contaminated with processing chemicals, degrading their performance. However the new method makes it possible to fabricate hundreds of individual carbon nanotube devices within 3 hours, an over ten times increase in efficiency.
Most importantly, these fabricated devices do not contain degrading processing chemicals on their surface. These so-called ultra-clean devices have been previously even more difficult to manufacture than regular single carbon nanotube transistors.
‘These clean devices help us to measure the intrinsic material properties. And the large number of devices helps to get a more systematic understanding of the nanomaterials, rather than just a few data points.’ says Dr. Nan Wei, a postdoctoral researcher in the group.
This study shows the aerosol-based nanotubes are superb in terms of their electronic quality, their ability to conduct electricity is almost as good as theoretically possible for SWCNTs.
More importantly, the new method can also contribute to applied research. One example is that by studying the conducting property of SWCNT bundle transistors, scientists may find ways to improve performance of flexible conductive films. This could prove useful for designers trying to build flexible, smash-proof phones. Follow-up work by the groups in Japan and Finland is already underway.
The article was published in “Advanced Functional Materials” in November 2019. You can read about it here http://dx.doi.org/10.1002/adfm.201907150
Reesarchers
- Published:
- Updated:
Read more news
Find our doctoral community at Aalto Social
Follow the posts, share and discuss anything related to doctoral education at Aalto Social.Aalto computer scientists in CHI 2024
Multiple papers from Aalto CS were accepted to the CHI 2024 conference
A peek into research on electrospinning of Functional Polysaccharide Derivatives
We had the honour of hosting a guest speaker, researcher Issei Otsuka, from the University of Grenoble Alpes at our ‘Coffee and Science’ event. Dr. Otsuka is visiting Finland on Researcher Short Mobility program which is aimed for the establishment of scientific partnerships between France and Finland.