Synchrotron radiation X-ray was used to carry out the grazing incidence small angle X-ray scattering(GISAXS)studies on GeSi quantum dots(QDs).The QDs sample was grown by molecular beam epitaxy method.Is-GISAXS program was used to simulate the GISAXS experiment data

the input parameters such as shape

size and inter-islands distance were obtained from atomic force microscopy observation

and the Distorted Wave Born Ap-proximation theory and appropriate distribution function were employed to simulate the 1D and 2D GISAXS experi-ment pattern.The simulated results fit the experiment data very well

which proves that the GISAXS is an effective method to probe the microstructure information about shape

size

and distribution of GeSi QDs.