Datensatz

Zusammenfassung

Ta-oxide thin films are shown to catalyse carbon nanotube growth by chemical vapour deposition. A low film thickness, the nature of the support material (best results with SiO2) and an atmospheric process gas pressure are of key importance for successful nanotube nucleation. Strong material interactions, such as silicide formation, inhibit nanotube growth. In-situ X-ray photoelectron spectroscopy indicates that no catalyst reduction to a metal or carbide occurs during nanotube growth and that the catalytically active phase is the Ta-oxide phase. Such a reductionfree oxide catalyst can be advantageous for integration of nanotubes into electronics.