2021   01   en   p.63-68 S.Sh. Gahramanov1, Y.A. Abdullayev1, A.A. Badalov1, K.M. Jafarli1, N.A. Abdullayev1,2, K.Sh. Gahramanov1,
The fermi level tuning by annealing in selenium vapor and argon plasma etching of Bi2Se3 surfaces


In the near-surface area of Bi2Se3 crystals, in order to reduce concentration of charge carriers and Se vacancies, which are electronic donors, annealing in selenium vapor was used. It has been established that the most optimal mode is annealing at a temperature of 100-150 °C for 70 hours. Effective impact on the surface condition with an identical purpose is exerted by processing the sample in a glow discharge in an argon medium. It was determined that treatment with an ions dose of ~1,1·1017 ion/cm-2, both after and without preliminary treatments in the form of annealing or chemical etching, leads to a significant decrease in concentration of carriers in crystals near-surface area.

Keywords: concentration of carriers, Se vacancies, annealing, selenium vapor, discharge, argon medium, treatment, ions dose, chemical etching.
PACS: 78.20.Jq, 78.68.+m,

Received: 16.02.2021


1. Institute of Physics of ANAS, AZ1143, H.Javid ave., 131, Baku, Azerbaijan
2. Baku State University, AZ1148, Z. Khalilov str., 23, Baku, Azerbaijan
E-mail: samir.gahramanov@gmail.com

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