Friday, January 09, 2009
Carbon nanotube ink with 10 times the electron mobility of typical organic semiconductors has been developed using a new chemical process that helps solve the thorny problem of manufacturing nanotube thin films. DuPont and Cornell University researchers claim 100 square centimeter per volt-second electron mobilities for its new process, compared to 10 square centimeters per volt-second for typical organic semiconductors. Current manufacturing processes for carbon nanotubes create a mixture of both semiconducting and metallic nanotubes, degrading the quality of thin-film transistors. DuPont claims to have solved that problem with a simple chemical treatment process called cycloaddition that uses fluorine molecules to negate the effects of metallic nanotubes. The result is pure semiconducting films.
BOTTOM LINE: DuPont's process could enable organic semiconducting thin films of carbon nanotubes to be printed at low temperatures on cheap flexible plastic substrates. If DuPont can bring its process to market, then semiconducting nanotubes could be cheaply mass produced for flexible electronics and plastic solar cells. However, 100 square centimeter per volt-second electron mobilities are still 100-times less than silicon-chip mobilities, so don't expect silicon to be obsoleted any time soon.
Posted by R. Colin Johnson at 10:34 AM