Adsorption of Bismuth on Si(110) Surfaces Studied by Scanning Tunneling Microscopy

Bi-adsorbed Si(110) surfaces are investigated by scanning tunneling microscopy (STM). The 2×3 structures where two protrusions are observed in a unit cell at the positive and negative sample bias voltages are formed at 700 K. The up and down terraces of the clean 16×2 structure still remain when Bi atoms are deposited at room temperature, while a rather flat surface with boundaries parallel to [-1, 1, 2] (or [1, -1, 2]) is formed by the adsorption of Bi at 570 K. The 2×3 structures of short-range order are also formed on the flat surface at 570 K.