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Kopach, Oleh

Publications and source records attributed to Kopach, Oleh.

Electrophysical Properties of Cd 0.96 Mn 0.04 Te 0.96 Se 0.04 Surface-Barrier Diodes

Diode structures, obtained by vacuum deposition of Al onto the surface of a p-Cd 0.96 Mn 0.04 Te 0.96 Se 0.04 single crystals, have been manufactured and studied. Applying the Sah-Noyce–Shockley carrier generation-recombination model, a quantitative description of the electrical characteristics of diodes has been achieved. Here, the resistivity of p-Cd 0.96 Mn 0.04 Te 0.96 Se 0.04 crystals was equal to ρ ≈ 400 Ω⋅cm and was determined from the I–V characteristics of the structure with two ohmic contacts, which were obtained by chemical deposition of gold. The activation energy of the dark temperature dependence of resistivity ρ=ρ(T) was equal to ΔE≈0.24 eV. The forbidden gap of p-Cd 0.96 Mn 0.04 Te 0.96 Se 0.04 crystals, found from the optical absorption spectra, was equal to E g =1.495 eV.

42 ENGINEERING↗

Melting and crystallization peculiarities in Cd0.50Mn0.50Te solid solutions

We investigated melting and crystallization processes of Cd0.50Mn0.50Te. Using differential thermal analysis (DTA) we studied the solid-liquid equilibrium temperature range, the temperature dependence of the volume fraction of the solid phase in the melt, and crystallization peculiarities. We observed that changing a dwell temperature from 1346 to 1354 K results in an increase of the crystallization temperature of the Cd0.50Mn0.50Te melt. Since the melt is in a semi-liquid state, its crystallization occurs over a solid-phase domain. It was found that a slightly overheated Cd0.50Mn0.50Te melt (up to 10 K) crystallizes more slowly than more overheated melts, and that the Cd0.50Mn0.50Te solid solutions are in a semi-liquid state in the temperature range of 1338 – 1354 K.

Kopach, Oleh↗