Discharge-free synthesis of vertically aligned carbon nanofibers
Vertically aligned carbon nanofibers (VACNFs) are the result of growing individual carbon nanofibers in a deterministic process which precisely defines their diameter, length, position, and alignment. The deterministic characteristics of the process are provided by the catalyst particles from which the growth is initiated. The combination of the outstanding mechanical and electrical properties of the VACNFs and their deterministic synthesis renders them an excellent choice as a basic building block of nanoelectromechanical systems (NEMS) with future applications for electronics and sensors. VACNFs are most commonly grown in a direct-current plasma enhanced CVD (dc PECVD) process. In spite of the maturity of this growth technique, it still suffers from plasma instabilities (discharges) when applied for device fabrication. A possible solution to overcome this problem is to adopt a pulsed plasma source instead.
The aim of this work is to develop a discharge-free dc PECVD growth process for the newly installed growth equipment (AIXTRON Black Magic). This growth process must be further optimized to yield high level of uniformity in terms of length and diameter of the VACNF. The reproducibility of the growth process is also of great importance and must be addressed. The ambition is furthermore that the projects should aim at generating publications in highly ranked scientific journals.
Description of work and learning outcome
The synthesis of VACNFs will be carried out on specially designed chips which are known to create plasma instabilities during nominal growth conditions. These plasma instabilities should be addressed by employing the pulse plasma source instead of the direct current one. The pulse plasma conditions should be then optimized to yield suitable VACNFs that can be incorporated in device fabrication. Acquaintance with the carbon based nanotechnology with an emphasis on VACNFs is the main learning outcome of the project. A comprehensive knowledge in synthesis of VACNFs by PECVD method is expected to be achieved by the end of the project. In addition this project will give experience of working in a cleanroom facility, operating a Scanning Electron Microscope (SEM), and writing for academic publication.
Last modified: May 26, 2009
Responsible for this page: Per Lundgren