Deposition of heteroepitaxial layers of topological insulator Bi sub(2)Se sub(3) in the trimethylbismuth-isopropylselenide-hydrogen system on the (0001) Al sub(2)O sub(3) and (100) GaAs substrates

Thin solid layers that are formed upon heating of the gaseous trimethylbismuth-isopropylselenide-hydrogen system on the (0001) Al sub(2)O sub(3) and singular and vicinal (100) GaAs surfaces are studied. The conditions for deposition of metal Bi and phases of Bi sub(4)Se sub(3), BiSe, and topological insulator Bi sub(2)Se sub(3) using the MOCVD method are determined. Pure metastable phase BiSe is obtained for the first time. Bi sub(2)Se sub(3) films with a thickness of no less than 200 nm, a relatively low volume concentration of 3 10 super(18) cm super(-3), and a high mobility of carriers at 300 K (1000 cm super(2) V super(-1) s super(-1)) are fabricated.