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

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