Surface structure of In/Si(1 1 1) studied by reflection high-energy positron diffraction

We have investigated a quasi-one-dimensional structure of In/Si(1 1 1) surface using reflection high-energy positron diffraction (RHEPD), which is sensitive to the topmost surface structure under the total reflection condition. From the rocking curves, we found that In atoms are located at two different vertical positions, i.e., 0.99 إ and 0.55 إ from the Si zigzag chain in both 4 × 1 (210 K) and 8 × 2 (60 K) phases.