Ohmic contacts to nitrogen-doped nanocarbon layers on diamond (100) surfaces

The transfer length method (TLM) was used to investigate Ohmic contact properties using the tri-layer stack Ti/ Pt/Au on a nitrogen-doped n-type conducting nanocarbon (nanoC) layer grown on a diamond (100) substrate. Room temperature electrical measurements were taken, and samples were annealed to observe changes in electrical conductivity. Low specific contact resistivity values between the electrode and nanoC layer of 8 x 10-5 omega cm2 were achieved, which is almost two orders of magnitude lower than previously reported values. The results were attributed to the increased nitrogen incorporation, and the presence of electrically active defects which leads to an increase in conduction in the nanocarbon film.