Tuesday, January 09, 2007

US Patent 7160532 - Nanotube Array on Metal Substrate

http://www.freepatentsonline.com/7160532.pdf

Carbon nanotube arrays are generally formed on non-metallic substrates since metallic substrates create difficulty in growing nanotubes that are pure and straight. However, in applications requiring a high current source to the nanotubes a metallic substrate would be useful as an electrode. This patent from Hon Hai Precision discloses a method of nanotube array fabrication on metal substrates. Claims 1 and 12 read:

1. A method for forming a carbon nanotube array, comprising the following steps: providing a metal substrate; oxidizing the substrate to form an oxidized layer on a surface of the substrate; depositing a catalyst layer on the oxidized layer; and introducing a carbon source gas; whereby the carbon nanotube array formed extends from the metal substrate.

12. A carbon nanotube array subassembly comprising: a metal substrate; and a carbon nanotube array formed thereon; wherein a material of the metal substrate is selected from the group consisting of tantalum, nickel, silver and steel, the metal substrate having an upper face, the upper face being oxidized to form an oxidized layer thereon.