While carbon nanotubes offer great promise, especially since they can theoretically carry 1,000 times more electric current than a metal conductor of the same size, new research conducted by the United States National Institute of Standards and Technology (NIST) suggests that device reliability is a major issue. NIST researchers fabricated and tested numerous nanotube interconnects between metal electrodes and found that the metal electrodes fail when currents rise above a certain threshold. Moreover, the nanotubes can sustain extremely high current densities for several hours, but then slowly degrade under constant current. The NIST work offers an early look at how these materials may behave in real electronic devices over the long term. Mark Strus, a NIST postdoctoral researcher, said, “The common link is that we really need to study the interfaces,” such as the intersections between the nanotubes and metals and between different nanotubes. Strus adds that despite the reliability concerns, the carbon nanotube networks may ultimately be useful for some electronic applications: “For instance, carbon nanotube networks may not be the replacement for copper in logic or memory devices, but they may turn out to be interconnects for flexible electronic displays or photovoltaics.”
http://www.nist.gov/mml/materials_reliability/cnt-081611.cfm