Rhombohedral Epitaxy of Cubic Silicon Germanium Semiconductors

摘要

Lattice matched semiconductors are very important in the development of microelectronic and optical devices because similar lattice constants can remove misfit dislocation defects. A research team led by Sang H. Choi at NASA Langley Research Center found a new way to grow the cubic Silicon Germanium (SiGe) semiconductors on a trigonal basal plane of sapphire crystal substrate, which is commonly described in a hexagonal frame. The technology uses new, innovative X-ray diffraction methods to stabilize the growth of rhombohedrally aligned SiGe crystals on sapphire crystals. About 99% single crystalline phase was achieved with NASA's new material growth scheme and characterization methods.