In 2 S 3 thin films are prepared by chemical bath deposition (CBD) technique to be applied as buffer layer in CdTe solar cells. CdTe photovoltaic devices are developed using In 2 S 3 as "standard buffer layer" in order to reduce the CdS thickness used as window material. It is important to examine potential thin films in a prospective life cycle study, focusing on direct costs, resource availability, and environmental impacts. Open and closed CBD system influence on the In 2 S 3 physical properties is analyzed. Stable tetragonal β-In 2 S 3 phase was confirmed by X-ray diffraction. Electrical properties were determined by four-point probe technique obtaining a resistivity value of 10 2 Ω cm. CdTe solar cells performance was studied by measuring J-V characteristics and spectral quantum efficiencies. These results reveal In 2 S 3 thin films as buffer layer reduce the cadmium quantity used in solar cells manufacture and improve their current collection in blue wavelength region (300-500 nm).

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Optical absorption and magnetic susceptibility data of the Zn 1Ϫx Mn x Ga 2 Se 4 family of compounds have been collected in the temperature range 10-300 K. One of the most interesting aspects of this series is the availability of samples in the whole composition range, in contrast with most diluted magnetic semiconductors that are only miscible in a limited range of compositions. Temperature-independent absorption bands with maxima at 2.33, 2.49, and 2.66 eV have been found that are assigned to electron transitions from the 6 A 1 ground state to the 4 T 1 , 4 T 2 , and 4 A 1 , or 4 E excited states of the Mn ϩϩ ion in a tetrahedral crystalline field. The optical spectra exhibit a temperature dependent absorption edge in the 350-600 nm region that corresponds to a direct band gap. The band gap energy has been determined as a function of atomic concentration and temperature. At room temperature, the variation of the energy gap E g with the Mn content shows a rather anomalous behavior that consists of an initial decrease for xϽ0.1, followed by a roughly flat variation for 0.1ϽxϽ0.5, and a nearly linear increase for xϾ0.5. An analogous evolution of E g with x is found when decreasing temperature. Such behavior has been compared with that reported for analogous systems. The variation of E g with temperature follows Varshni's relation for all compositions. A monotonic increase of the magnetic susceptibility with x is found within the whole range of Mn content.

Los recubrimientos de aluminio-silicio fueron depositados sobre el acero inoxidable AISI 316 mediante deposición química de vapor en lecho fluidizado (CVD-FBR), en el rango de temperaturas de 540 a 560 ºC, utilizando un lecho formado por 2,5 g de silicio y 7,5 g de aluminio en polvo, y 90 g de lecho inerte (Alúmina), el cual se hizo fluidizar con Ar. Como gases activadores se usó una mezcla de HCl/H₂, en relaciones de 1/10 a 1/16. Además, se varió el tiempo de deposición de los recubrimientos de 45 minutos a 1.5 horas, con una relación en volumen de 50% de gases activos y 50% de gases neutros. Se realizó una simulación termodinámica con la ayuda del programa informático Thermocalc, para obtener información de la posible composición y cantidad de material depositado, para las condiciones seleccionadas. En los recubrimientos se encuentran FeAl₂Si, Fe₂Al₅ y FeAl₂. Los recubrimientos aluminio-silicio fueron tratados térmicamente, para mejorar sus propiedades mecánicas y su comportamiento frente a la oxidación, por la interdifusión de los elementos de aleación, ya que el tratamiento térmico hace que el aluminio difunda hacia el substrato, y el hierro difunda hacia la superficie del recubrimiento, logrando la transformación de los compuestos anteriores en FeAl, Al₂FeSi, Cr₃Si, AlCrFe y AlFeNi.