【Abstract】 Among the three main methods for the s ynthesis of carbon nanotubes(CNTs ),chemical vapor deposition(CVD)has received a great deal of attentio n since CNTs can be synthesized at sig nificantly low temperature.Plasma chemical vapor deposition me thods can synthesize CNTs at lower te mperature than thermal CVD.But in th e usual catalytic growth of CNTs by CVD,CNTs are often tangled together and have some defects.These will limit t he property research and potential applications.How to synthesize the str aight CNTs at low temperature become s a challenging issue.In this letter,s traight carbon nanotube(CNT)films were achieved by microwave pla sma chemical vapor deposition(MWPCVD)catalyzed by round Fe-Co-Ni alloy particles on Ni substrate at 610℃.It wa s found that,in our experimental condition,the uniform growth rate along the circumference of round alloy particles plays a very important role in the gro wth of straight CNT films.And because the substrate is conducting,the straight CNT films grown at low temperature ma y have the benefit for property research and offer the possibility to use t hem in the future applications.更多还原