IMPURITY-MEDIATED GROWTH AND CHARACTERIZATION OF THIN PSEUDOMORPHIC GERMANIUM LAYERS IN SILICON

We deposited thin germanium layers (among 4 and 12 monolayers thick) in silicon with antimony-mediated molecular beam epitaxy. All layers were investigated with Raman spectroscopy, electroreflectance measurements, and transmission electron microscopy in the lattice-imaging mode. The layers are continuous, no islanding could be observed even for the 1.8-nm-thick layers. Raman spectroscopic and electroreflectance measurements indicate some relaxation of the strained Ge layers. The interface between germanium layers and silicon buffer and cap layer are not sharp; significant intermixing could be detected.