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Electrical properties, steady-state photoconductivity, and kinetics of photoconductivity have been studied in the samples of polycrystalline p-CdTe (as-grown by the method of low-temperature synthesis from thoroughly purified components; subjected to subsequent annealing in Cd vapors; and aged at room temperature). It is shown that electrical properties of as-grown p-CdTe are controlled by a complex defect with the level at Ev + 0.16 eV; the latter transforms into the level Ev + 0.25 eV as a result of annealing in Cd vapors and aging of the samples. In addition, the deep centers with the levels Ev + 0.6 eV and Ev + 0.86 eV were detected; these centers govern the decay of the photocurrent.

Low-temperature (5K) photoluminescence of silicon substrates in the range 0.8–1.2 eV is studied before and after deposition of polycrystalline diamond films. The diamond films were deposited in the microwave plasma onto high-purity dislocation-free silicon (with the resitivity ρ ≈ 3 kΩ cm) subjected to mechanical polishing or more delicate chemical and mechanical polishing. The deposition temperature was 750–850°C. In the photoluminescence spectra of the samples with the substrates polished chemically and mechanically, two lines, D1 and D2, corresponding to the dislocation-related emission are recorded. Generation of dislocations in the substrates is caused by efficient adhesion of the diamond film and, as a result, by internal stresses that relax with the formation of dislocations. The experimental spectra are practically identical to the photoluminescence spectra observed in silicon (ρ ≈ 100 Ω cm) with the density of dislocations ∼104 cm−2.

Propagation of nonequilibrium acoustic phonons in ZnTe single crystals at helium temperature was studied with phonons being both optically generated and produced by a metal-film heater. Experiments with [110] ZnTe allowed for the detection of the arrival of longitudinal and transverse acoustic phonons, which are particularly well resolved when generated by a heated metal film. A bolometer also detected emission of ZnTe material with a time constant τ ∼ 90 ns, which can apparently be attributed to the luminescence of oxygen complexes, because the lifetimes of other complexes and bound excitons are substantially shorter.