LEED observation of 4 × 1-In superstructure prepared on Si(111)-quasi-5 × 5-Cu surface

The surface structure of {Cu, In} binary system on Si(111) has been studied with the low energy electron diffraction (LEED) technique. First, the quasi-‘5 × 5’-Cu structure can be prepared with the deposition of 1–2.5 ML of Cu on the clean surface of Si at temperatures of 300–550°C. With the additional deposition of 0.5-1.6 ML of In, the surface structure changes into a 4 × 1 structure at temperatures between 400 and 500°C. At 550°C, however, the ‘5 × 5’-Cu structure does not disappear, despite of the supply of In vapor.