4H-SiC Carbon-face (C-face) epitaxial layers have been grown by a low-pressure, horizontal hot-wall type chemical vapor deposition system. The site-competition behavior is observed in the doping process of the C-face epitaxial growth. This site-competition behavior depends on the growth pressure. Specular surface was obtained at a substrate temperature of 1600degreesC and C/Si ratios less than 3 with a buffer layer grown by the C/Si ratioof 0.6. The residual donor concentration decreases with lowering the growth pressure. The lowest residual donor concentration of 2 x 10(14) cm(-3) was obtained on an epitaxial layer grown at a C/Si ratio of 3 and a growth pressure of 60 mbar. Hall effect measurement indicates grown C-face epitaxial layers have the crystalline quality as high as that of the Si-face epitaxial layer. The electron mobility of the obtained C-face epitaxial layer with N-d-N-a I x 10(15) cm(-3) was 956 cm(2)/Vs at 293 K and 41700 cm(2)/Vs at 40 K.