EFFECT OF FIXED PARTICLES ON PERIODIC ADATOM ARRANGEMENTS ON SI(111) UNRECONSTRUCTED SURFACES

Time-independent and -dependent Monte Carlo simulations of a two-dimen sional lattice gas were performed to investigate the effect of fixed p articles on periodic adatom arrangements on Si(111) 1 X 1 surfaces. In both the simulations introducing fixed particles, domains of the peri odic structures were divided into small fragments around them. This ca n be explained by the fixed particles reducing the degree of freedom o f the adatom configurations so the number of ways of reaching the unif orm configuration is highly restricted. Based on the simulations, we p redict that a large 1 X 1 region without any obstacle impurities is de sirable to obtain a large periodic structure of Si adatoms. (C) 1998 E lsevier Science B.V. All rights reserved.