Plasma enhanced chemical vapor deposition(PE-CVD) method has an advantage in synthesizing carbon nanotubes(CNTs) at lower temperature compared with thermal enhanced chemical vapor deposition(TE-CVD) method. In this study, CNTs was prepared by using PE-CVD method. The growth rate of CNT was faster more than 100 times on using Invar alloy than iron as catalyst. It was found that chrome silicide was formed at the interface between chrome layer and silicon substrate which should be considered in designing process. Nanoparticles of Invar catalyst were found oxidized on their surfaces with a depth of 10 m. Microstructure was analyzed by scanning electron microscopy, transmission electron microscopy, scanning transmission electron microscopy, and energy dispersive x-ray spectrometry. Based on the result of analysis, growth mechanism at an initial stage was suggested.