Scanning tunneling microscopy observation of surface superstructures during the growth of In on In/Si(111) surface

Surface superstructures are studied with scanning tunneling microscopy during the growth of In on In/Si(111). On the inhomogeneous substrate of Si(111) 4 × 1/3×3-In coexisting surface, the deposition of 1.5 monolayer (ML) In at about 0 °C leads to 7×3 reconstruction on 3×3 surface and the formation of one-dimensional nanowires on 4 × 1 surface (1.0 ML = 7.8 × 1014 atoms/cm2). Subsequent deposition of In at − 100 °C gives rise to the appearance of a hexagonal superstructure with 37×43 periodicity on 7×3 reconstructed surface, while self-alignment of In dots along one-dimensional nanowires is observed on the initial 4 × 1 surface. On Si(111) 3×3-In surface, the growth of 2.5 ML In at about − 100 °C yields 6 × 6 superstructure. The strain in the epitaxial In thin films provides a driving force for the formation of self-organized surface structures.