Carbon nanotube-Si diode as a detector of mid-infrared illumination

摘要

We report a room temperature mid-infrared photodetector based on a carbon nanotube-siliconnheterojunction nanostructure. The observed mid-infrared band u00018–12 u0001mu0002 in the photocurrentnspectrum is consistent with the estimated band gap energy of semiconducting multiwall nanotubesnu000115 to 30 nm diameteru0002. The fast response time u000116 msu0002 and small temperature changenu0001u000310−8nKu0002 upon infrared light suggest that the photocurrent response is not due to bolometricneffect. We determined that the primary mechanism of the photocurrent in this spectral range isnassociated with photon absorption of semiconducting multiwalled carbon nanotubes followed byncharge separation at the interface, their transport, and collection at the external electrodes.n© 2010 American Institute of Physics. u0004doi:10.1063/1.3279141