Ge(111) 7 × 7 surface structure induced by Sn

When tin was deposited by 0.3–0.8 monolayer thick on Ge(111) clean surface at room temperature and annealed at 345°C, 7 × 7 superlattice structure appeared on the surface. Features of the diffraction pattern of the 7 × 7 structure are strikingly similar to those of the diffraction pattern of Si(111) 7 × 7 surface structure, which suggests that atomic arrangements in the two 7 × 7 structures resemble each other very well.