The concentration dependence of acceptor-state radii in p-Hg0.78Cd0.22Te crystals

Semiconductors - Tập 35 - Trang 33-39 - 2001
V. V. Bogoboyashchii1
1Kremenchuk State Polytechnical Institute, Kremenchuk, Ukraine

Tóm tắt

Hopping conduction in undoped p-Hg0.78Cd0.22Te crystals containing native double-charged acceptors (Hg vacancies) with concentrations of 1016–1018cm−3 was studied. Electrical conduction with a variable hopping range is dominant in the entire concentration range at temperatures below 6–16 K. The measured parameters of this conduction were used to calculate the acceptor-state radius as a function of vacancy concentration N A . It is shown that, for N A <4×1017 cm−3, the low-temperature conduction occurs via the vacancy states whose radius is independent of N A . For N A >5×1017 cm−3, the hopping conduction is governed by the states of uncontrolled shallow-level impurity acceptors. The radius of the state for these defects increases with increasing N A owing to an increase in the effective permittivity of the medium.

Tài liệu tham khảo

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