Monocrystalline 3C-SiC layers were synthesized by atmospheric pressure chemical vapor deposition on Si(1 1 1) substrates using SiH4 and C3H8 gases at temperatures between 1350degreesC and 1400degreesC. Both atomic force microscopy and X-ray diffraction spectroscopy measurements reveal a notable dependence of surface morphology and layer quality on the C/Si ratio in the gas phase during experiment. In particular, three types of surface morphologies have been observed: (i) rough, (ii) mirror-like and (iii) pyramidal defect covered, attributed to lack of C, C limited growth and stacking faults generation, respectively. From Raman spectral peak shifts, a tensile strain state of the SiC films, lower for the 1400degreesC grown series, was found. (C) 2003 Elsevier Science B.V. All rights reserved.