An Investigation on Structural and Optical Properties of Zn<i>_1-x</i>Mg<i>_x</i>S Thin Films Deposited by RF Magnetron Co-Sputtering Technique

• Main Authors: Muhammad Shahriar Bashar, Yulisa Yusoff, Siti Fazlili Abdullah, Mashudur Rahaman, Puvaneswaran Chelvanathan, Abdul Gafur, Farid Ahmed, Md Akhtaruzzaman, Nowshad Amin
• Format: Article
• Language: English
• Published: MDPI AG 2020-08-01
• Series: Coatings
• Subjects: Zn<i>_1-x</i>Mg<i>_x</i>S; sputtering; XRD; UV-Vis-NIR
• Online Access: https://www.mdpi.com/2079-6412/10/8/766
• ISSN: 2079-6412

In this paper, Zn<i>_1-x</i>Mg<i>_x</i>S thin films were co-sputtered on glass substrates using ZnS and MgS binary target materials under various applied RF power. The compositional ratio of Zn<i>_1-x</i>Mg<i>_x</i>S films was varied by changing the RF power at an elevated temperature of 200 °C. The structural and optical properties were studied in detail. The structural analysis shows that the co-sputtered Zn<i>_1-x</i>Mg<i>_x</i>S thin films have a cubic phase with preferred orientation along the (111) plane. The lattice constant and ionicity suggest the presence of a zincblende structure in Zn<i>_1-x</i>Mg<i>_x</i>S thin films. Zn<i>_1-x</i>Mg<i>_x</i>S thin films have transmittance over 76%. The extrapolation of optical characteristics indicates that direct bandgaps, ranging from 4.39 to 3.25 eV, have been achieved for the grown Zn<i>_1-x</i>Mg<i>_x</i>S films, which are desirable for buffer or window layers of thin film photovoltaics.