Processing and Study of Optical and Electrical Properties of (Mg, Al) Co-Doped ZnO Thin Films Prepared by RF Magnetron Sputtering for Photovoltaic Application

Chayma Abed; Susana Fernández; Selma Aouida; Habib Elhouichet; Fernando Priego; Yolanda Castro; M B Gómez-Mancebo; Carmen Munuera

doi:10.3390/ma13092146

Processing and Study of Optical and Electrical Properties of (Mg, Al) Co-Doped ZnO Thin Films Prepared by RF Magnetron Sputtering for Photovoltaic Application

Materials (Basel). 2020 May 6;13(9):2146. doi: 10.3390/ma13092146.

Authors

Chayma Abed¹, Susana Fernández², Selma Aouida³, Habib Elhouichet^{4

5}, Fernando Priego⁶, Yolanda Castro⁶, M B Gómez-Mancebo⁷, Carmen Munuera⁸

Affiliations

¹ Department of Physics, University of Tunis El Manar, 2092 Tunis, Tunisia.
² Energy Department, CIEMAT, 28040 Madrid, Spain.
³ Laboratoire de Photovoltaïque, Centre de Recherches et des Technologies de l'Energie, BP 95, Technopôle de Borj-Cedria, 2050 Hammam-Lif, Tunis, Tunisia.
⁴ Physics Department, College of Sciences, University of Bisha, Saudi Arabia, P.B. 551, Bisha 61922, Saudi Arabia.
⁵ Laboratoire de Caractérisations, Applications et Modélisation des Matériaux LR18ES08, Sciences Faculty of Tunis, University of Tunis El Manar, 2092 Tunis, Tunisia.
⁶ Glass Department, Institute of Ceramics and Glass (CSIC), Campus Cantoblanco, 28048 Madrid, Spain.
⁷ Chemistry Division, CIEMAT, 28040 Madrid, Spain.
⁸ Instituto de Ciencia de Materiales de Madrid-CSIC (ICMM), 28049 Madrid, Spain.

Abstract

In this study, high transparent thin films were prepared by radio frequency (RF) magnetron sputtering from a conventional solid state target based on ZnO:MgO:Al₂O₃ (10:2 wt %) material. The films were deposited on glass and silicon substrates at the different working pressures of 0.21, 0.61, 0.83 and 1 Pa, 300 °C and 250 W of power. X-ray diffraction patterns (XRD), atomic force microscopy (AFM), UV-vis absorption and Hall effect measurements were used to evaluate the structural, optical, morphological and electrical properties of thin films as a function of the working pressure. The optical properties of the films, such as the refractive index, the extinction coefficient and the band gap energy were systematically studied. The optical band gap of thin films was estimated from the calculated absorption coefficient. That parameter, ranged from 3.921 to 3.655 eV, was hardly influenced by the working pressure. On the other hand, the lowest resistivity of 8.8 × 10^-2 Ω cm^-1 was achieved by the sample deposited at the lowest working pressure of 0.21 Pa. This film exhibited the best optoelectronic properties. All these data revealed that the prepared thin layers would offer a good capability to be used in photovoltaic applications.

Keywords: Al doped ZnO-MgO powder; RF magnetron sputtering; optoelectronic properties; photovoltaic applications; solid-state method; thin films; working pressure.