Experimental evidence of aluminum induced in situ crystallization of amorphous SiC is presented. The deposition of SiC films on Si substrates was performed using low pressure chemical vapor deposition method at 600 °C with concurrent supply of Al(CH3)3 and H3SiCH3. Transmission electron micrographs confirm the presence of nanocrystals, whereas capacitance-voltage measurements demonstrate that the deposited films are p type doped. A crystallization mechanism is proposed based on the classic theory of nucleation in the growth rate limited regime. The introduction of Al(CH3)3 enhances the surface reaction and increases the supersaturation, which reduces the activation energy for nucleation.