Abstract: A Ge/Si(001) island multilayer structure is investigated by double crystal X-ray diffraction,transmission electron microscopy,and atomic force microscopy.We fit the satellite peaks in the rocking curve by two Lorentz lineshapes,which originate from the wetting layer region and the island region.Then from the ratio of the thicknesses of the Si and Ge (GeSi) layers as determined by TEM,the Ge compositions of the wetting layer and islands are estimated to be about 0.51 and 0.67,respectively,according to the positions of the fitted peaks.This proves to be a relatively simple way to investigate the Ge/Si (001) island multilayer structure.

Key words: Si, Ge, nano-dot, island, X-ray