Studying the Structure and Lifetime of Photogenerated Current Carriers of Cadmium Telluride-Based Solid Solutions in CdTe–Sb2Te3 and CdTe–CdSb Systems.

The structure of CdTe–Sb2Te3 and CdTe–CdSb solid solutions (0–1019 Sb atoms cm–3) prepared by multistage solid-state synthesis from the elements has been studied. It has been found that the introduction of antimony Sb3+ and Sb3− into cadmium telluride leads to a decrease and increase in the unit cell volume, respectively. It has been shown that the crystal lattice parameters gradually change up to an antimony concentration of 1018 atoms cm–3 in both systems, whereas an increase in the antimony concentration above 1018 Sb atoms cm–3 is characterized by an abrupt change in the unit cell volume due to a significant change in the structure. The decay kinetics of current carriers has been studied by the time-resolved microwave photoconductivity method. It has been found that the introduction of antimony into CdTe in a threshold concentration (1018 Sb atoms cm–3) leads to an increase in the lifetime of photogenerated current carriers; this fact can be attributed to the formation of defect associates and the occurrence of a self-compensation process during doping. [ABSTRACT FROM AUTHOR]