Specific features of the low-temperature conductivity and photoconductivity of CuInSe2-ZnIn2Se4 alloys

n-type CuInSe₂-ZnIn₂Se₄ alloy single crystals are grown by the horizontal variant of the Bridgman method. The slight temperature dependence of the conductivity, high electron concentration, and the low photoconductivity of single crystals containing a low (5–10 mol %) fraction of ZnIn₂Se₄ are indicative of the nearly degenerate state of the crystals. It is established that, in the CuInSe₂-ZnIn₂Se₄ single crystals containing 15 and 20 mol % of ZnIn₂Se₄, the hopping mechanism of conductivity is dominant at temperatures of T ～ 27–110 K. At T ≥ 110 K, hopping conductivity gives way to activated conductivity. It is found that the specific feature of the low-temperature (27–77 K) photoconductivity spectrum of single crystals with ～15 and 20 mol % of ZnIn₂Se₄ is a single narrow peak at a wavelength of λ_max = 1190–1160 nm.