In prior research, a possibility to increase the growth rate of the low-temperature epitaxial growth of 4H-SiC was explored by supplementing chloro-carbon precursor CH3Cl with HCl as an additional source of chlorine. In the current work, SiCl4 was investigated as a replacement for SiH4+HCl. The homogeneous nucleation in the gas phase was further reduced compared to SiH4+HCl growth, thus essentially eliminating the main bottleneck for increasing the growth rate (R-g). However, for low values of the carrier gas flow, premature dissociation of Si gas-phase clusters was found to cause R-g nonhomogeneity and triangular defect formation. The drastically suppressed homogeneous nucleation opened the window for increasing the carrier gas flow velocity in order to improve the R-g homogeneity from upstream to downstream. Nevertheless, generation of triangular defects was significant at R-g above 5-6 mu m/h. The process window for obtaining good epilayer morphology was found to correspond to Si supply-limited mode. The window was restricted at low values of C/Si ratio by formation of Si-rich islands/droplet and at high C/Si ratio by formation of polycrystalline SiC. The process window became increasingly narrower at higher R-g, which serves as a new bottleneck for significantly increasing R-g at such low growth temperatures. (C) 2009 Elsevier B.V. All rights reserved.