Abstract :
The combination of Raman spectroscopy and molecular beam epitaxial (MBE) growth can supply valuable additional information on interface and layer formation. Here the growth of CdS on InP(100), that of undoped and nitrogen doped ZnSe on GaAs(100) as well as the nitridation of GaAs(100) serve as examples for the usefulness of this in situ and on line technique. In particular, evidence for a reaction in the initial phase of CdS/InP(100) interface formation and the transformation from the cubic to the hexagonal phase of CdS at around 200 nm layer thickness is provided. In the case of ZnSe growth on GaAs(100) the incorporation of nitrogen in the layer results in a deterioration of the ZnSe layer crystallinity together with the appearance of compressive strain in the GaAs substrate. The latter is assigned to nitrogen diffusion into the substrate which is further supported by a nitridation experiment of GaAs which also leads to the formation of a thin layer of GaN. Moreover, the underlying substrate is heavily disturbed as can be judged from the detection of As cluster.
