THE INITIAL-STAGES OF EPITAXIAL-GROWTH OF SILICON ON SI(100)-2 X-1

Epitaxial growth of Si on Si(100)-2 x 1 has been studied in a temperature range from 290 to 820 K using spot profile analysis of LEED. Intensity and profile of several diffraction spots at different energies have been measured simultaneously with deposition in UHV at a rate of about 1 monolayer in 3 min. During growth at 640 K the surface is rough, there are 4 layers growing simultaneously. The anisotropy of the broadening of the 00-beam was taken into account for the determination of the layer distribution. The islands are elongated parallel to the dimer-rows. Already during the deposition of the first monolayer the final shape of the islands is formed. The average island size during layer-by-layer growth is 30 x 10 atoms. For T = 290 to 400 K deposited atoms cannot cross step edges, so that surface roughness increase rapidly during growth. For T > 750 K the crystal grows via step-propagation.