In this paper we demonstrate the large area deposition of n-type conductive nanocrystalline diamond thin films on p-type Si substrates. We show that adding N-2 into CH4/H-2/CO2 gas mixture allows a wide controlling of diamond film morphology from micro- to nanocrystalline, blockstone-like or porouslike morphology potentially suitable for various applications. Moreover, after adding we found that the diamond films revealed a deep level with activation energy of 0.44 +/- 0.03 eV. (C) 2014 Elsevier B.V. All rights reserved.