Improving the Electrical Contact Property of Single-Walled Carbon Nanotube Arrays by Electrodeposition

A parallel method for the fabrication of metal contacts on single-walled carbon nanotube (SWNT) arrays was presented and the electrical contact property was evaluated by a SWNT-field effect transistor structure. Copper and gold contacts were fabricated on both semiconducting SWNTs and metallic SWNTs by using a maskless electrodeposition process. The SWNT array remained a p-type semiconductor after the electrodeposition. The contact resistance between SWNT array and microelectrodes was reduced more than 50% by the established copper contacts. The source-drain current of the carbon nanotube field-effect transistor (CNT-FET) structure can be further increased from 7.9 μA to 9.2 μA when the copper contacts were replaced by gold ones, which is probably due to the better contact property to SWNT of gold contacts with fine grain size.