Effect of very thin SiC layer on heteroepitaxial growth of cubic GaN on Si (001)

We have investigated the effect of very thin SiC layer formation on Si (001) for cubic GaN growth by RF plasma-assisted molecular beam epitaxy. It is found that a cubic GaN film can be epitaxially grown on Si (001) covered with an approximately 2.5-nm-thick cubic SIC layer, while GaN grown on Si (001) without such an SIC layer results in the polycrystal growth of a predominantly hexagonal phase. In the latter case, an approximately 1-nm-thick amorphous Si layer is formed at the interface between GaN and Si by the irradiation of nitrogen plasma.