Molecular beam epitaxy growth of PbSe on BaF2-coated Si(111) and observation of the PbSe growth interface

摘要: Epitaxial growth of PbSe/BaF2/CaF2 heterostructures was carried out by molecular beam epitaxy (MBE) on Si(111) wafers. Successful transfer 3-μm-thick PbSe epilayers accomplished bonding the MBE-grown samples face down to polished copper plates followed removal silicon substrate dissolving BaF2 buffer layer in water. High-resolution x-ray diffraction measurements demonstrated that epilayer maintained high-crystalline quality after transfer. In addition, optical Nomarski characterization exposed interface showed sets parallel straight step lines consistent with glide dislocations primary {100}〈110〉 system. Such features are evidence large thermal expansion mismatch strain occurred these layers.