By using scanning tunneling microscopy (STM) we have studied the growth of
the unfaulted 1 x 1 reconstructed H-terminated domains on the expense of th
e surface area of the faulted 1 x 1 domains upon adsorption of atomic H on
Si(1 1 1)7 x 7. In contrast to previous investigations, we describe the tra
nsformation of the surface towards a one-domain H-terminated structure in 1
x 1 geometry as a thermally activated process which is not directly induce
d by H adsorption. The limitations in achieving a perfect surface are relat
ed to the beginning desorption of H at around 680 K. (C) 2001 Elsevier Scie
nce B.V. All rights reserved.