Probing the growth dynamics of cobalt films on Si(001) surfaces by STM

Abstract

<P>THE GROWTH OF CO ON SI(001) WAS OBSERVED BY STM TO ADOPT PSEUDO LAYER-BY-LAYER GROWTH MODE ON CLEAN MULTI-DOMAIN SI(001) SURFACE WHEN DEPOSITED AT ROOM TEMPERATURE. INTRA-DIMER BRIDGE SITE 1 OF THE SI A?? (2X1) SURFACE WAS FOUND TO BE THE PREFERRED ADSORPTION SITE OF CO. THE 2D CO LAYER TRANSITS INTO 3D COSI2 ISLANDS THAT ELONGATE WITH EQUAL PROBABILITY IN [110] AND [1 -10] DIRECTIONS ON THE SAME SI A?? (2X1) DOMAIN OF THE FLAT SI(001) SURFACE UPON ANNEALING TO 550A?C. LEED PATTERN SHOWING C(2X2) SURFACE PERIODICITY WAS OBSERVED AS A CONSEQUENCE OF THE SILICIDATION. HOWEVER, PREFERENTIAL ELONGATION OF 3D COSI2 ISLANDS ALONG THE [1 -10] DIRECTION COEXISTING WITH A NEW TYPE OF COSI2 ISLANDS, IS OBSERVED ON THE 6A? VICINAL SI(001) SURFACE. THIS SUGGESTS THAT THE A??TEMPLATINGA?? EFFECT OF THE VICINAL SUBSTRATE INDUCES DIFFUSION ANISOTROPY OF CO AND SI PROMOTING GROWTH OF COSI2 ISLANDS IN THE [1 -10].</P>