In this paper, we present a novel process for the realization of large area, low cost field emission cathodes. The process makes use of alumina substrates, which are anodically oxidized in order to yield porous structures capable of hosting metal catalyst nanoparticles. By carefully controlling the final stage of the anodisation as well as the electrodeposition conditions, it is possible to fine tune the density of such catalysts in the range of 10~8-10~9cm~2. The catalytic growth of CNTs is subsequently performed at low temperature (～ 600°C or below, thanks to the use of H_2O), using plasma enhanced chemical vapour deposition. There is no lithography need to make the cathode and current densities of ～ 1mA/cm~2 are easily obtained.
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