THE INITIAL-STAGES OF AG AG(100) HOMOEPITAXY - SCANNING-TUNNELING-MICROSCOPY EXPERIMENTS AND MONTE-CARLO SIMULATIONS/

Results are presented of a scanning tunneling microscopy study of Ag/A g(100) homoepitaxy. We examine both submonolayer nucleation and growth of two-dimensional islands, for temperatures between 295 and 370 K, a nd the initial stages of multilayer kinetic roughening at 295 K. Compa rison with results of Monte Carlo simulations for an appropriate model for metal(100) homoepitaxy produces estimates of 330 +/- 5 meV for th e terrace diffusion barrier, and an effective value of 30 +/- 5 meV fo r the additional step-edge barrier (assuming a common prefactor of 10( 12)/s). We also assess adatom-adatom bonding by analyzing the transiti on from irreversible to reversible island formation.