SiC-4H Epitaxial Layer Growth Using Trichlorosilane (TCS) as Silicon Precursor
4H-SiC epitaxial layers have been grown using trichlorosilane (TCS) as the silicon precursor source together with ethylene as the carbon precursor source. A higher C/Si ratio is necessary compared with the silane/ethylene system. This ratio has to be reduced especially at higher Si/H2 ratio because the step-bunching effect occurs. From the comparison with the process that uses silane as the silicon precursor, a 15% higher growth rate has been found using TCS (trichlorosilane) at the same Si/H2 ratio. Furthermore, in the TCS process, the presence of chlorine, that reduces the possibility of silicon droplet formation, allows to use a high Si/H2 ratio and then to reach high growth rates (16 *m/h). The obtained results on the growth rates, the surface roughness and the crystal quality are very promising.
Robert P. Devaty, David J. Larkin and Stephen E. Saddow
S. Leone et al., "SiC-4H Epitaxial Layer Growth Using Trichlorosilane (TCS) as Silicon Precursor", Materials Science Forum, Vols. 527-529, pp. 179-182, 2006