Study of semiconductor super thin heterostructures with synchrotron radiation X-ray standing wave technique

The X-ray standing wave experiment method is established with the double-crystal monochromator and precision 2-circle goniometer at Beijing Synchrotron Radiation Facility. It is used combined with the X-ray diffraction, to investigate the heterostructure of super thin Ge atomic layer within Si crystals. The results show that the GexSi1-x alloy layer with average x = 0.13 was formed in the Si crystal sample due to the segregation of Ge atoms during the preparation. Due to the diffusion of Ge atoms to the crystal surface, the GexSi1-x alloy layer was disappeared and nearly pure Ge layer was formed on the Si crystal surface after annealing at 650 degree C