Catalyst free low temperature direct growth of carbon nanotubes on SiGe islands and Ge quantum dots

Uchino, T., Bourdakos, K.N., Ashburn, P., de Groot, C.H., Kiziroglou, M.E. and Smith, D.C. (2005) Catalyst free low temperature direct growth of carbon nanotubes on SiGe islands and Ge quantum dots. 6th International Conference on the Science and Application of Nanotubes, NT05, Gothenburg, Sweden. 25 - 30 Jun 2005.

Abstract

A metal catalyst free growth method of carbon nanotubes (CNTs) has been developed using chemical vapor deposition (CVD) of CNTs on carbon implanted SiGe islands on Si substrates. From SEM and Raman measurements, the fabricated CNTs are identified as single walled CNTs (SWNTs) with diameter ranging from 1.2 to 1.6 nm. Thick and curly oxide nanofibers were also obtained as a by-product of the growth process but could be dissolved using HF treatment. Essential parts of the substrate preparation after CVD SiGe growth and carbon implant are a chemical oxidization by hydrogen peroxide solution and a heat treatment at 1000 °C prior to CNT growth. We believe that these processes enhance surface decomposition and assist the formation of carbon clusters, which play a role in seeding CNT growth. Though further investigation is required to improve the density of the SWNTs, the growth technique would be a practical technique for growing metal-free CNTs for a variety of applications, while at the same time opening up the prospect of merging CNT devices into silicon VLSI technology. We will also present results that demonstrate the application of this CNT growth technique to germanium quantum dot substrates.

This record has no associated files available for download.

Contributors

Author: C.H. de Groot

Download statistics