Download or read book High Efficiency Cadmium and Zinc Telluride-based Thin Film Solar Cells written by and published by . This book was released on 1990 with total page 83 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polycrystalline Cd{sub 1-x}Zn(subscript x)Te and Cd{sub 1-x}Mn(subscript x)Te films with a band gap of 1.7 eV were successfully grown on glass/SnO2/CdS substrates by molecular beam epitaxy (MBE) and metal-organic chemical vapor deposition (MOCVD), respectively. Polycrystalline Cd{sub 1-x}Zn(subscript x)Te films grown by MBE resulted in uniform composition and sharp interfaces. However, polycrystalline Cd{sub 1-x}Mn(subscript x)Te films grown by MOCVD showed nonuniform compositions and evidence of manganese accumulation at the Cd{sub 1-x}Mn(subscript x)Te/CdS interface. We found that manganese interdiffuses and replaces cadmium in the CdS film. By improving the CdTe/CdS interface and, thus, reducing the collection function effects, the efficiency of the MOCVD CdTe cell can be improved to about 13.5%. MBE-grown CdTe cells also produced 8%--9% efficiencies. The standard CdTe process was not optimum for ternary films and resulted in a decrease in the band gap. Recent results indicate that CdCl2 + ZnCl2 chemical treatment may prevent the band-gap reduction, and that chromate etch (rather than bromine etch) may provide the solution to contact resistance in the ternary cells.