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V. Melnik et al.
Fig. 10 SPV decay curves in ZnO/Si excited with LED light of wavelengths λ = 405 nm (a),
470 nm (b) and 860 nm (c). The light pulse width is 1 μs. The thickness of ZnO films is 11 (curve
1), 22 (2), 43 (3), 67 (4), 70 (5), and 120 nm (6)
to 67 nm. When further increasing the thickness to 120 nm, the decay rate of the SPV
signal remains nearly unchanged. At the same time, when the thickness increases
from 11 to 43 nm, the SPV amplitude value first increases monotonically and then
begins to decrease for greater thicknesses (up to 120 nm).
If the same samples are excited by light pulses of 10 ns duration from a nitrogen
laser (λ = 337.1 nm), the decay curves shown in Fig. 11 are observed. Under these
V. Melnik et al.
Fig. 10 SPV decay curves in ZnO/Si excited with LED light of wavelengths λ = 405 nm (a),
470 nm (b) and 860 nm (c). The light pulse width is 1 μs. The thickness of ZnO films is 11 (curve
1), 22 (2), 43 (3), 67 (4), 70 (5), and 120 nm (6)
to 67 nm. When further increasing the thickness to 120 nm, the decay rate of the SPV
signal remains nearly unchanged. At the same time, when the thickness increases
from 11 to 43 nm, the SPV amplitude value first increases monotonically and then
begins to decrease for greater thicknesses (up to 120 nm).
If the same samples are excited by light pulses of 10 ns duration from a nitrogen
laser (λ = 337.1 nm), the decay curves shown in Fig. 11 are observed. Under these