Two advanced research methods: Frequency-time-resolved microwave photoconductivity and broadband photodielectric spectroscopy

Two known methods of research of electric properties were applied on semiconducting materials and their methodology was significantly improved to obtain quantitative data on elementary reactions of charge carriers. The resonator method of microwave photoconductivity included the measurements of the frequency dependences of photoresponse. The modified frequency- and time-resolved microwave photoconductivity method gives the opportunity to separate contributions to a photoresponse of the free electrons which did not experience capture by acceptors and structural defects, and the electrons which are again released in a free state from traps. The use of a light source (λ = 350 ÷ 2500 nm) together with a broadband dielectric spectrometer provides an effective tool (the broadband photodielectric spectroscopy—BPDS) for research of relaxation processes in semiconductors caused by excess current carriers. Examples of investigation of the photoelectric properties of CdS, CdTe, and Cu(In,Ga)Se2 received with modified methods are presented.