Surface structure of selenium-treated GaAs (001) studied by field ion scanning tunneling microscopy

Abstract

For a selenium-treated GaAs (001) surface followed by heat treatment at ∼530 °C, we have observed using field ion scanning tunneling microscopy ordered arrays with regular intervals of 4×periodicity in the [1̄10] direction (1.6 nm) to line up in the [110] direction. These ordered arrays are in good agreement with the 4×1 structure previously observed by other methods. In a closer view, the 4×structure was found to be formed by closely placed double rows.

Optimization of the Growth of the Van der Waals Materials Bi2Se3 and (Bi0.5In0.5)2Se3 by Molecular Beam Epitaxy

“…It is reported that the surface structure changed from 2 × 4 to 2 × 1 while lowering the substrate temperature, before applying selenium flux . After the selenium deposition, the film can be further heat-treated to show a stable 4 × 1 or 2 × 3 structure. A similar 1 × 1 to 4 × 1 reconstruction has been seen in a GaAs (001) substrate passivated with an aqueous selenium-based reagent when heated up to 580°C .…”