The diffusion of Si adsorbates which were deposited onto a (001) surface was investigated by using reflection electron microscopy. At temperatures of up to about 600C, the diffused length of the adsorbates was proportional to the fourth root of the heating time; up to a critical value. At heating times shorter than the the critical one, the diffused length was determined by the distance at which atoms collided with each other on the surface. At heating times longer than the critical one, the diffused length was proportional to the square root of the heating time and the diffusion length was governed by thermal diffusion of the adsorbates.

T.Doi, M.Ichikawa, S.Hosoki: Applied Physics Letters, 1997, 71[14], 1993-5