Deposition of epitaxial β–SiC films on porous Si(100) from MTS in a hot wall LPCVD reactor

Abstract

Epitaxial β-SiC thin films were grown on modified Si(100) substrates from methyltrichlorosilane (CH3SiCl3 or MTS) in a hot wall reactor by using low pressure chemical vapor deposition (LPCVD). At 1150 °C, the growth rate of the β-SiC films was 120 Å/min. Epitaxial β-SiC(100) thin films were deposited after the deposition time of 12.5 min. However, the crystallinity of the deposited films was influenced by the deposition time. For example, the occurrence of rotational β-SiC(100) crystals and polycrystalline β-SiC with a highly preferred orientation of (100) planes was obtained for the deposition time of 50 min. XRD and TEM showed the appearance of polycrystalline β-SiC films with a preferred orientation of β-SiC(111) after further increasing the deposition times (time ≥ 75 min). At 1100 °C, polycrystalline β-SiC films with poor surface morphology were observed even though the film had a preferred orientation of β-SiC(100) for short deposition time (e.g., 12.5 min). Polycrystalline β-SiC(111) film was obtained for the deposition time of 200 min at this temperature.