Scaling law and dynamical exponent in the Volmer-Weber growth mode: Silver on GaAs(001)2 × 4

The growth of Ag deposited onto the GaAs(001)2 x 4 has been investigated by means of scanning tunnelling microscopy. Silver forms islands (Volmer-Weber growth) whose average dimension increases according to Theta(1/z) (with z = 4.2). Theta being the number of Ag atoms deposited at constant rate onto GaAs. The Ag islands exhibit a hut shape with 210 and 310 facets. The kinetic of surface coverage has been measured and the Avrami exponent, 12, has been determined, finding n = 0.61. Both z and n are related to the dynamic nature of the growth process. (C) 2000 Elsevier Science S.A. All rights reserved