Van der Waals xenotaxy: Oriented growth of hexagonal GaSe(001) on rectangular GaAs(110)

The growth of the layered chalcogenide GaSe on cleaved GaAs(110) surfaces was investigated with photoemission and low-energy electron diffraction (LEED). GaSe films grow with their c axis perpendicular to the GaAs(110) surface. LEED patterns after initial film growth are a superposition of rectangular GaAs:Se spots and two hexagonal domains rotated by ±5° with respect to the GaAs ⟨001⟩ axis. At higher film thickness a hexagonal LEED pattern with GaSe〈120〉 ‖ GaAs 〈001〉 is obtained.