Structural, optical and electrical properties of Ni-doped CdS thin films prepared by spray pyrolysis

• Published in: Journal of alloys and compounds 2013-04, Vol.557, p.53-59
• Main Authors: Rmili, A., Ouachtari, F., Bouaoud, A., Louardi, A., Chtouki, T., Elidrissi, B., Erguig, H.
• Format: Article
• Language: English
• Subjects: Cadmium; CdS thin films; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Deposition; Dopants; Electrical properties; Electrical properties of specific thin films; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Ni-doped CdS; Nickel; Optical; Optical properties; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of specific thin films; Physics; Spray coating techniques; Spray pyrolysis; Structural; Thin films
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2012.12.136

► We prepared Ni–CdS thin films by a facile spray pyrolysis using perfume atomizer on glass substrate. ► We studied the effect of [Ni]/[Cd] ratio on the structural, morphological, optical and electrical properties of Ni-doped CdS thin films. ► CdS thin films doped with 4% Ni showed high transmittance of about 80% in the visible and near infrared regions, and relatively low resistivity of 1.3×105Ωcm. Un-doped and Ni-doped cadmium sulphide (Ni–CdS) thin films were prepared by spray pyrolysis technique using perfume atomizer, from aqueous solution of hydrated cadmium chloride (CdCl2⋅H2O) and thiourea (CS(NH2)2 as sources of cadmium and sulphur ions respectively. We used hexahydrated nickel chloride (NiCl2⋅6H2O) as the dopant. The films were deposited on heated amorphous glass substrates at 400°C. The effect of the [Ni]/[Cd] ratio on the structural, morphological, optical and electrical properties of these films was investigated. X-ray diffraction (XRD) studies revealed that all the deposited films (un-doped and Ni-doped CdS) were polycrystalline with hexagonal structure and exhibited [101] preferential orientation. The scanning electron microscopy (SEM) images showed a dense surface structure composed of crystallites whose average size decreases when the [Ni]/[Cd] ratio increases. The optical study showed that all the films were highly transparent. The transmittance in the visible region varies between 70% and 85%, depending on the dopant concentration. The film obtained with the [Ni]/[Cd] ratio equal to 4at.% Ni showed minimum resistivity of 1.3×105Ωcm at room temperature.