Sulfiding effects on ZnS thin films obtained by evaporation technique

• Published in: Vacuum Vol. 130; pp. 154 - 158
• Main Authors: Martínez-Martínez, S., Mayén-Hernández, S.A., de Moure-Flores, F., Arenas-Arrocena, Ma.C., Campos-González, E., Zamora-Antuñano, M.A., Arellano-Badillo, V.M., Santos-Cruz, J.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-08-2016
• Subjects: Annealing; Atmospheres; Graphite; Heat treatment; Non-toxic material; PVD; Stoichiometry; Sulfur; Sulfurizing annealing treatments; Thin films; Zinc sulfides; Non-toxic material; Sulfurizing annealing treatments; PVD
• ISSN: 0042-207X; 1879-2715
• DOI: 10.1016/j.vacuum.2016.05.011

ZnS thin films were grown on a glass substrate using physical vapor deposition techniques at room temperature. Subsequently, the thin films were annealed in three different atmospheres: vacuum, nitrogen-sulfur and vacuum-sulfur. In order to sulfurize the thermal treatment atmosphere within CSS equipment, a graphite box was designed that maintained sulfur in its steam phase while all of the intervals of temperatures were tested. In addition, during the annealing pure ultra-high nitrogen gas was used. It was found that heat treatment is indispensable in nitrogen-sulfur and vacuum-sulfur atmospheres in order to increase the polycrystallinity and stoichiometry of ZnS thin films. The polycrystalline nature and pure phase were determined by XRD technique. The EDS results showed that the films annealed in a sulfur atmosphere were close to stoichiometry and that direct band gap varied from 3.68 to 3.84 eV. The most effective atmosphere was nitrogen-sulfur, showing enhancement in the optical, structural, and morphological properties.
•ZnS thin films are produced by PVD technique and annealed in a vacuum, vacuum-sulfur and nitrogen-sulfur atmospheres.•A modified Close Space Sublimation equipment with a graphite box was utilized for the sulfurated annealed treatments.•Thermal sulfurated annealed treatments are indispensable to increase the structural properties.•Atmospheres of nitrogen-sulfur and vacuum-sulfur respectively, exhibits the improved of structural and optical properties.