in the dielectric material 20 to a filamentary metal network structure containing insulator nano cluster a metal catalyst content higher than the percolation threshold leads to an electrical conduction in the material 18 which is typical of metals and for the growth of large carbon nanotubes 24 densely packed for a metal catalyst content lower than the percolation threshold the electron conduction occurs by activated mechanisms such as electron tunneling and or electron hopping and the dependence of the catalyst electrical conductivity on temperature becomes non linear when a potential is applied across the electrodes 14 and 16 in the range of 5 to 20 volts and more preferably of 10 volts electrons will percolate through the material 18 generally from one electrode to the other the percolation of electrons may be thought of as u201c hopping u201d or tunneling through the dielectric material 20 from one catalytic particle 22 to another following the path of lowest activation energy or least resistance some of the electrons will be u201c hopping u201d to the catalytic particles 22 that are positioned on or at the surface 26 current transport across the electrode 14 and 16 within the material 18 may be explained by substrate assisted tunneling the electrons transfer between metal.