Lattice accommodation of low-index planes: Ag(111) on Si(001)

Deposition of nonreacting metals on semiconductors usually results in three-dimensional islands that often exhibit a different crystal orientation than the substrate. Using the kinetic pathway of low temperature growth, a continuous and smooth Ag film with a (111) orientation is formed on Si(001). The interface planes fit nearly exactly within a (3×{}4) unit cell of the Si(001) surface. The remaining small mismatch is adjusted by periodic arrays of interfacial defects. The orientation of the Ag(111) film is strictly determined by the orientation of the Si bonds: From step to step of the Si(001) substrate the Ag(111) crystallites rotate by 90 ^∘{}.