Synthesis of vertically aligned carbon nanotubes on submicron-sized dot-catalyst array using plasma CVD method

Vertically aligned carbon nanotubes were synthesized on submicron-sized dot-catalyst array which have a dot size of 400 nm and dot intervals varying from 0.3 μm to 10 μm, using direct current plasma enhanced chemical vapour deposition(PECVD) method. The dot-catalyst array was fabricated by lift-off process using electron beam lithography. Field emission characteristics were measured and compared for different dot intervals. Experimental results of field emission characteristics and the Fowler–Nordheim plots suggest that spatial control of dotted-catalyst is very important to improve the electric field emission characteristics. The results show that the highest field enhancement factor β was obtained when the dot interval was two times longer than the length of CNTs.