Spontaneous vacancy array formation on FeSi[sub 2] and CoSi[sub 2] formed on Si(100) 2×n surface.

Atomic structure of FeSi[sub 2] or CoSi[sub 2] grown on the Si(100) 2xn surface has been investigated by scanning tunneling microscopy. After annealing the Fe or Co covered Si(100) 2xn substrate at ∼800 °C, an ordered adatom vacancy array appears on the nominal 1x1 surface of the formed FeSi[sub 2] or CoSi[sub 2] islands, which has not been observed for silicide on the Si(100)-2xl. Upon further annealing to ∼ll00 °C, the vacancies coalesce into striped domains along one of the <011> directions. These nanostructured features are a result of the Ni impurities, and can be a promising template for fabricating nanodot arrays. [ABSTRACT FROM AUTHOR]