Producing a stable catalyst for nanotube growth

Abstract

A process (40) is provided for preparing a catalyst (20). A catalyst (20) is formed over a substrate (12). A gas (24) comprising hydrogen and carbon is applied to the catalyst (20), wherein a carbon seeding layer (26) is formed on the catalyst (20). Carbon nanotubes (28) may then be grown from the catalyst (20) having the carbon seeding layer thereon (26).

Description

FIELD OF THE INVENTION [0001] The present invention generally relates to a catalytic process for growing carbon nanotubes and more particularly to a process for producing a stable and highly reactive catalyst for carbon nanotube growth. BACKGROUND OF THE INVENTION [0002] Carbon is one of the most important known elements and can be combined with oxygen, hydrogen, nitrogen and the like. Carbon has four known unique crystalline structures including diamond, graphite, fullerene and carbon nanotubes. In particular, carbon nanotubes refer to a helical tubular structure grown with a single wall or multi-wall, and commonly referred to as single-walled nanotubes (SWNTs), or multi-walled nanotubes (MWNTs), respectively. These types of structures are obtained by rolling a sheet formed of a plurality of hexagons. The sheet is formed by combining each carbon atom thereof with three neighboring carbon atoms to form a helical tube. Carbon nanotubes typically have a diameter in the order of a frac...

AI Technical Summary

Benefits of technology

The patent describes a process for making a catalyst by adding a gas with hydrogen and carbon to a substrate with a layer of catalyst. This results in the growth of carbon nanotubes from the catalyst. The technical effect of this process is the creation of a highly effective catalyst for chemical reactions.

Problems solved by technology

Unfortunately, these methods typically yield bulk materials with tangled nanotubes.

However, the choice of catalyst materials that can be used to promote SWNT growth in a CVD process has typically been limited to Fe / Mo nanoparticles.

Furthermore, the catalytic nanoparticles were usually derived by wet chemical routes, which are time consuming and difficult to use for patterning small features.

However, the required high growth temperature prevents integration of CNTs growth with other device fabrication processes.

However, this must be done immediately prior to growing the nanotubes and depending on the CNT growth technique and process conditions employed, such as thermal versus plasma enhanced, active gas composition, gas temperature, not all of the oxidation is removed.

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