Structure determination of three-dimensional hafnium silicide nano structures on Si(1 0 0) by means of X-ray photoelectron diffraction

We propose a modified zirconium silicide model for the structure of HfSi2 islands on Si(1 0 0). We studied this system in a combined investigation by means of photoelectron diffraction (XPD), photoelectron spectroscopy and atomic force microscopy. Synchrotron radiation was used for enhanced energy resolution and surface sensitivity. Calculated XPD patterns of model clusters reflecting the structure as well as the morphology of the islands exhibit an excellent agreement with the experimental results. From LEED and AFM measurements a preferential nano structure growth along the [0 1 1] and [01¯1] direction was observed. Complementary XPD results clearly show that the HfSi2 structures are silicon terminated.