Metal-supported high crystalline Bi₂Se₃ quintuple layers

Atomically flat thin films of Bi₂Se₃ were grown on Au(111) metal substrate using molecular beam epitaxy. Hexagonal atomic structures and quintuple layer steps were observed at the surfaces of grown films using scanning tunneling microscopy. Multiple sharp peaks from (003) family layers were characterized by x-ray diffraction measurements. The atomic stoichiometry of Bi and Se was considered using x-ray photoemission spectroscopy. Moiré patterns were obtained at the surfaces of one quintuple layer films due to lattice mismatch between Bi₂Se ₃ and Au. Our experiments suggest that Au is a reasonable material for electrodes in Bi₂Se₃ devices.