Effect of tin content on the electrical and optical properties of sprayed silver sulfide semiconductor thin films

• Published in: Materials science in semiconductor processing 2013-12, Vol.16 (6), p.1584-1591
• Main Authors: Boughalmi, R., Boukhachem, A., Gaied, I., Boubaker, K., Bouhafs, M., Amlouk, M.
• Format: Article
• Language: English
• Subjects: Ag2S; Applied sciences; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Deposition; Doping; Energy gap; Energy transmission; Exact sciences and technology; Hardness; Materials science; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metals. Metallurgy; Methods of deposition of films and coatings; film growth and epitaxy; Optical constants: refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of bulk materials and thin films; Physics; Production techniques; Semiconductors; Silver; Spray coating techniques; Spray pyrolysis technique; Surface treatment; Thin films; Tin; XRD
• ISSN: 1369-8001; 1873-4081
• DOI: 10.1016/j.mssp.2013.05.019

Silver sulfide (Ag2S) thin films have been deposited on glass substrates by t spray pyrolysis using an aqueous solution which contains silver acetate and thiourea as precursors. The depositions were carried out at a substrate temperature of 250°C. Structural studies by means of X-ray diffraction show that all tin (Sn)-doped Ag2S thin films crystallized in a monoclinic space group with noticeable changes in the crystallites' orientation. The discussion of some structural calculated constants has been made with Sn doping in terms of microhardness measurements. Moreover, the optical analysis via the transmittance, reflectance as well as the photocurrent reveals that the direct band gap energy (Egd) decreases (Egd varies from 2.34 to 2.16eV) and the indirect band gap energy (Egi) increases (Egi varies from 0.98 to 1.09eV) slightly as a function of Sn content. Electrical study shows that Sn doping changes the electrical conductivity and proves the thermal activation of electrical conduction.