Carbon nanotube: An indirect ~ 0 eV band gap material

Thin film of carbon was synthesized from camphor (C10H16O) by CVD technique in hydrogen atmosphere. For the first time it is confirmed the presence of almost zero indirect band gap in addition to its direct band gap.. Carrier concentration with intrinsic carbon is found to be around 1021 n/cm3. It is suggested that unless the zero indirect band gap is increased carbon thin film cannot be used for making a p:n junction. XRD, Raman and SEM analysis are performed.