Carbon nanotube field-effect devices with asymmetric electrode configuration by contact geometry

摘要

We have studied experimentally the conductive properties of single walled carbon nanotube(SWNT) based field-effect type devices, with different contact geometries at the connectingelectrode. The device designs are asymmetric with one end of the SWNT having the metalelectrode deposited on top and immersing it, while at the other end, the SWNT is on top of theelectrode. The devices were made with either gold or palladium as electrode materials, of whichthe latter resulted in different behavior of the different contact types. This is argued to be caused bythe existence of a thin insulating layer of surface adsorbents on the palladium, possibly Pd5O4, theeffect of which is enhanced by the 1D nature of the contact area in the configuration with SWNTon top of electrode.