| Autor: |
V.E. Sizov, B.S. Shchamkhalova, G. G. Yakushcheva, A. G. Temiryazev, V.A. Jitov, P. I. Kuznetsov, V. A. Luzanov |
| Rok vydání: |
2015 |
| Předmět: |
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| Zdroj: |
Journal of Crystal Growth. 409:56-61 |
| ISSN: |
0022-0248 |
| Popis: |
We report on a metal organic vapor epitaxy (MOVPE) of Bi 2 Te 3− x Se x films over the entire range of compositions ( 0 ≤ x ≤ 3 ) for the first time. The films were grown on Al 2 O 3 (0001) substrates at 465 °C using trimethylbismuth (Bi 2 Me 3 ), diethyltellurium (Et 2 Te) and diisopropylselenium (iPro 2 Se) as metalorganic sources. To realize the 2D growth mode and to grow films with flat surfaces and high crystalline quality, a thin ZnTe buffer layer was used. As-grown films were studied using optical and AFM microscopy techniques and X-ray diffraction. It was found that under steady growth conditions the composition of Bi 2 Te 3− x Se x films strongly depends on the film thickness. But a high rate of interdiffusion of chalcogens at the growth temperature rapidly leads to a homogeneous composition of the film in the growth direction. Dependence of the intensity of X-ray reflection (0012) on the composition of Bi 2 Te 3− x Se x films x has extremes near x =1 ( Bi 2 Te 2 Se ) and x =2 ( Bi 2 Se 2 Te ) . The AFM micrographs and profiles show large (above 2 μm) triangle-shaped atomically flat terraces with step height of a quintuple layer (0.90 nm) of the tetradymite-type compounds. The electronic properties of the grown films have been characterized via four probe magnetotransport measurements. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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