Electronically enhanced surface diffusion during Ge growth on Si(100)

The effect of nanosecond pulsed laser excitation on surface diffusion during the growth of Ge on Si(100) at 250 degrees C was studied. In situ reflection high-energy electron diffraction was used to measure the surface diffusion coefficient while ex situ atomic force microscopy was used to probe the structure and morphology of the grown quantum dots. The results show that laser excitation of the substrate increases the surface diffusion during the growth of Ge on Si(100), changes the growth morphology, improves the crystalline structure of the grown quantum dots, and decreases their size distribution. A purely electronic mechanism of enhanced surface diffusion of the deposited Ge is proposed. (C) 2011 American Institute of Physics. [ doi: 10.1063/1.3567918]