As a substitute material for silicon, we synthesized few layer graphene (FLG) by CVD process with a 300-nm-thick nickel film deposited on the silicon substrate and found out the lowest temperature for graphene synthesis. Raman spectroscopy study showed that the D peak (wave length : ${sim}1,350;cm^{-1}$) of graphene was minimized and then the 2D one (wave length : ${sim}2,700;cm^{-1}$) appeared when rapid thermal anneal is carried out with the $C_2H_2$ treated nickel film. This study demonstrates that a high quality FLG formed at a low temperature of $400^{circ}C$ is applicable as CMOS devices and transparent electrode materials.