Erbium and Germanium Profiles in Si_(1-x)Ge_x Layers Grown by Silicon Sublimation-Source Molecular-Beam Epitaxy in GeH_4

摘要

The Ge and Er depth profiles in Si_(1-x)Ge_x layers grown on Si(100) substrates by Si sublimation-source molecular-beam epitaxy in GeH_4 were studied by secondary ion mass spectrometry. The results demonstrate that Ge facilitates Er incorporation into the growing Si-Ge layer. The Er dopant profile becomes sharper with increasing Ge content. The Ge profile also has rather sharp boundaries, indicating that there is no Ge surface segregation, which is attributable to the presence of adsorbed hydrogen, acting as a surfactant.