Resumo

CALIXTO-RODRIGUEZ, M.  e  SANCHEZ-JUAREZ, A.. Películas delgadas de SnS₂ preparadas por la técnica de Rocío Pirolítico. Superf. vacío [online]. 2007, vol.20, n.1, pp.34-38. ISSN 1665-3521.

In this work we present the results from the preparation and characterization of tin disulfide (SnS₂) thin films obtained by the spray pyrolysis technique. We used an alcohol, water, and hydrochloric acid mixture for the dissolution of the precursor compounds: SnCl₂ and N,N-dymetil thiourea, employed as sources of Sn and S ions, respectively. The substrate temperature was varied from 340 to 380°C in 20°C steps. From the XRD analysis we found that the deposited material was polycrystalline for substrate temperatures bigger than 340°C, with an hexagonal structure and a high degree of orientation along the [001] direction. We calculate the optical bandgap, E_g, of the deposited thin films with the data obtained from the optical characterization, the values are in the range 1.99-2.38 eV for indirect allowed optical transitions. The values of the electrical conductivity measured in the dark, σ_D, are in the range 10^-5-10^-7 (Ω cm)^-1. Films deposited at T_s = 360°C have the best structural and optical characteristics to be used in photovoltaic structures.

Palavras-chave : Thin films; Spray pyrolysis; Tin disulfide.