Well-aligned carbon nanotubes have been synthesized on Corning and silicon substrates at extremely low temperatures of 450 degreesC using a slightly modified conventional plasma enhanced chemical vapor deposition (PECVD). The deposition system was intentionally designed to impose mesh potential on the substrates through an external electrode that was a critical parameter for low temperature growth. Mixture gases of C2H2 and NH3 with the imposed mesh potential of about 50 V effectively aligned multi-wall carbon nanotubes at 450 degreesC on Ni-coated substrates.