Magneto-transport studies of Si/SiGe and Si/SiGeC quantum well structures grown by molecular beam epitaxy at low temperatures Available to Purchase

The magneto-transport properties of SiGe and SiGeC quantum well structures were studied in relation to their dependence on the growth temperature, Ge and C concentration, well width, and spacer width. It is found that interface roughness and charged impurities are the main origins for scattering in SiGe and SiGeC two-dimensional hole gas (2DHG) structures. Rapid thermal annealing subsequent to growth improves the mobility in SiGeC 2DHG by a factor of 2, whereas only a 20% increase is observed for SiGe 2DHG. At 1.6 K a mobility of $1930 cm2/V s$ for $Si0.81Ge0.185C0.05$ and $6900 cm2/V s$ for $Si0.85Ge0.15$ channels was deduced from Shubnikov–de Haas oscillations measured up to 8 T. The effective mass determined for holes in the SiGeC alloy is $0.21±0.02.$ B δ-doped Si layers were used to determine the B diffusion in the temperature range from 700 to 850 °C by intersubband absorption spectroscopy.