Antireflection coatings based on fluoride formulations for organic solar cells

An alloy of a mixture of fluorides MgF₂ and AlF₃ with CaF₂ has been obtained in a 3-kW solar furnace. It was supposed that a minor CaF₂ additive compensates for the tensile stresses appearing in thin MgF₂ and AlF₃ films, with their mechanical properties being thereby improved. The results of X-ray phase analysis demonstrated that both components of the mixture are present in the alloy, while the complex oxide CaAl₄O₇, the formation of which is attributed to the melting in air, is only identified in AlF₃: CaF₂ = 95: 5 (wt %). The increase in the transmittance of glass and polyethylene terephthalate upon deposition onto their surface of a thin film of the material synthesized in the study is due to the optical properties of AlF₃ and MgF₂.