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By solid-phase synthesis, macrocrystalline Cu2 − δZn2 − xSnxS4 − ySey monograin powders have been prepared, the chemical composition of which was shown by XRD and Raman spectroscopy to be different in powder fractions of different sizes formed during the synthesis. The influence of synthesis conditions on the decay kinetics of photogenerated charge carriers in different fractions has been studied using the frequency–time-resolved microwave photoconductivity method. The characteristic photoresponse half-life, τ1/2, increased with increasing grain size. The smallest values of the lifetime were observed for the fraction with sizes of 50–70 μm (τ1/2 <5 ns), and the largest values were for the fraction with a grain size of 70–90 μm (τ1/2 ~ 12 ns). [ABSTRACT FROM AUTHOR]

It can be seen from the figure that with a decrease in the copper content in the samples, the characteristic decay time of microwave photoconductivity decreases. 1 shows the normalized decays of microwave photoconductivity in Cu SB 2 sb CdSnS SB 4 sb (curve I 1 i ) and Cu SB 1.6 sb CdSnS SB 4 sb (curve I 2 i ) powders. Table 1 shows summary experimental data on the characteristic decay times of the "fast" and "slow" components of microwave photoresponse in the Cu SB 2- sb CdSnS SB 4 sb (0 <= <= 0.4) powders. [Extracted from the article]

The influence of the annealing treatment on the kinetics of the electron trapping processes in CdS thin films has been investigated using the contactless time-resolved microwave photoconductivity technique (TRMC) in 9 GHz band. The thin (<200 nm) CdS films were synthesized using two techniques: by the chemical deposition from the solution (CBD method) and by the pyrolysis of the aerosols of the aqueous solutions of the thiourea coordination compounds of cadmium (Cd(thio)2Cl2) on a heated substrate. Annealing in both the air and the nitrogen atmospheres resulted in an increase of the amplitude and characteristic decay time of the photoresponse. Two particular effects caused by the annealing treatments were observed: the structural improvement and the energy redistribution of the electron traps. [ABSTRACT FROM AUTHOR]