Scientific complications and controversies noted in the field of CdS/CdTe thin film solar cells and the way forward for further development

Cadmium telluride-based solar cell is the most successfully commercialised thin film solar cell today. The laboratory-scale small devices have achieved ~ 22%, and commercial solar panels have reached ~ 18% conversion efficiencies. However, there are various technical complications and some notable scientific contradictions that appear in the scientific literature published since the early 1970s. This review paper discusses some of these major complications and controversies in order to focus future research on issues of material growth and characterisation, post-growth processing, device architectures and interpretation of the results. Although CdTe can be grown using more than 14 different growth techniques, successful commercialisation has been taken place using close-space sublimation and electrodeposition techniques only. The experimental results presented in this review are mainly based on electrodeposition. Historical trends of research and commercial successes have also been discussed compared to the timeline of novel breakthroughs in this field. Deeper understanding of these issues may lead to further increase in conversion efficiencies of this solar cell. Some novel ideas for further development of thin film solar cells are also discussed towards the end of this paper

STUDY OF THE MORPHOLOGICAL AND ELECTRICAL PROPERTIES OF FILMS OF SOLID SOLUTION ZnXSn1-хSe OBTAINED BY THE METHOD OF CMBD

The ZnXSn1-XSe solid solution films were fabricated by the chemical molecular beam deposition (CMBD) method. The sources used were ZnSe and SnSe compounds of stoichiometric composition at the substrate temperature of 5600С. The morphological and electrophysical properties of the ZnXSn1-XSe solid solution films are investigated. Scanning electron microscope images showed that the grain sizes of the films are 8÷20 microns. The structural parameters of the obtained films are given. The electrical conductivity of the films was 15 ÷ 1 • 10-6 (Ohm·cm) -1 depending on the composition of the solid solution