Method for making carbon nanotubes
US10676359B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | May 14, 2018 |
| Grant date | Jun 9, 2020 |
| Priority date | — |
| Expiry date | Jul 3, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10K85/221
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method of making carbon nanotubes with equal or other ratio of semiconductive to conductive elements in integrated form includes: depositing a catalyst layer on a substrate and heating same in a reaction furnace to a predetermined temperature. A carbon source gas and a protective gas are introduced to grow a plurality of carbon nanotube segments, some carbon nanotube segments being conductive metallic. A positive electric field is applied to the plurality of carbon nanotube segments, wherein the catalyst layer is positively charged and the positive electric field is reversed to the negative, to grow a second carbon nanotube segment structure from the metallic carbon nanotube segments. The direction of the negative electric field is along a second direction and the second carbon nanotube segment structure then comprises a plurality of semiconducting carbon nanotube segments.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.