Quasi-Medium Energy Ion Scattering Spectroscopy Observation of a Ge δ-doped Layer Fabricated by Hydrogen Mediated Epitaxy

We have observed the behavior of Ge δ-doped layers in Si(001) by Quasi-medium energy ion scattering spectroscopy (Q-MEIS). The δ-doped layers were fabricated by hydrogen mediated epitaxy (HME) of Si. We found that, in the δ-doped layers fabricated by HME, the surface segregation of Ge atoms was reduced compared with that by conventional molecular beam epitaxy (MBE). The Ge atoms, however, were widely spread in the growing film. We assume that in the HME sample, hydrogen atoms are segregated to the top-most layer of the growth surface. Moreover, the Si buffer layer has a comparatively good crystalline quality in the HME sample.