Progress of IV-VI Semiconductor Research in China

Progress of IV-VI semiconductor (lead chalcogenides) research in China is reported. Lead chalcogenides (PbSe and PbTe) have been grown by molecular beam epitaxy (MBE). Evolution of PbSe surface morphologies with different Se/PbSe beam flux ratio has been studied by atomic force microscopy (AFM) and high-resolution x-ray diffraction (HRXRD). Interesting surface features, such as triangle holes and spirals with monolayer steps, are observed by AFM. Glide of threading dislocations in < 110> {100} -glide system and Pb-rich atom agglomeration play an important role in the formation of triangle pits. PbSe QDs grown by self-organization and mid-infrared luminescent emission of the QDs at room temperature are demonstrated. Phonon modes of PbTe and PbSe epitaxial film are studied by Raman spectroscopy in detail.