SI(111)-ROOT-3X-ROOT-3R30-DEGREES-SI MEDIATED BY HYDROGEN DESORPTION

A scanning tunneling microscopy (STM) study was carried out for a stru ctural change of the Si(111) surface induced by the desorption of hydr ogen (H-) atoms from hydrogenated Si-clusters on a Si(111)-1 x 1 : H s urface. After the complete desorption of the H-atoms, a new surface re construction of square-root 3 x square-root 3 R30-degrees: Si was foun d near 535-degrees-C, which is characterized by the Si-adatom arrangem ent at T4 sites on the Si(111)-1 x 1 surface. The appearance of this r econstruction can be explained by the redistribution of Si-adatom from the Si-clusters on Si(111)-1 x 1 surface during H-desorption.