Growth of group III nitrides on Si(111) by plasma-assisted molecular beam epitaxy

Wurtzitic single-crystal GaN and polycrystalline (columnar) InGaN have been grown on the Si(111) face in an electron cyclotron resonance plasma-assisted molecular beam epitaxy process. Reflection high-energy electron diffraction shows registry of the nitride basal-plane triangular lattice with respect to the Si(111) substrate triangular network. Plan-view transmission electron microscopy images reveal crystalline or polycrystalline GaN structure depending on growth temperature. High-resolution x-ray rocking curves of the (0002) peak were as narrow as 30 min for a 0.6-μm GaN film grown on a thin AlN buffer layer at 750 °C.