Characterization of epitaxial Si films grown by atmospheric pressure plasma chemical vapor deposition using cylindrical rotary electrode

Epitaxial Si films have been grown at low temperatures (500-700 degrees C) by atmospheric pressure plasma chemical vapor deposition using a cylindrical rotary electrode. The variation in Si film quality across the entire deposition area has been investigated. It is found that defect-free epitaxial Si growth is possible at 500 degrees C with sufficient plasma power in the central part of the film. At film edges, however, there are narrow regions of polycrystalline growth. From the deposition experiments under simplified boundary conditions (laminar gas flow and a uniform electric field in the plasma region), it is suggested that a large number of reactive precursors are generated when SiH4 molecules enter the plasma region, and the growth rate at the film edge on the upstream side is too high for the growth of single crystals. On the other hand, polycrystalline growth at the film edge on the downstream side is related to particle formation.