Physical Investigations of (Co, Mn) Co-Doped ZnO Nanocrystalline Films

Bechir Yahmadi; Olfa Kamoun; Badriyah Alhalaili; Safia Alleg; Ruxandra Vidu; Najoua Kamoun Turki

doi:10.3390/nano10081507

Physical Investigations of (Co, Mn) Co-Doped ZnO Nanocrystalline Films

Nanomaterials (Basel). 2020 Jul 31;10(8):1507. doi: 10.3390/nano10081507.

Authors

Bechir Yahmadi^{1

2}, Olfa Kamoun³, Badriyah Alhalaili⁴, Safia Alleg⁵, Ruxandra Vidu⁶, Najoua Kamoun Turki²

Affiliations

¹ Physics Department, Common First Year dean ship, Umm Al-Qura University, Makkah 21955, Saudi Arabia.
² Physics Laboratory of Condensed Matter, Faculty of Sciences of Tunis, Tunis El Manar University, Tunis 2092, Tunisia.
³ Physics of Semiconductor Devices Unit, Faculty of Sciences of Tunis, Tunis El Manar University, Tunis 2092, Tunisia.
⁴ Nanotechnology and Advanced Materials Program, Kuwait Institute for Scientific Research, Safat 13109, Kuwait.
⁵ Laboratoire de Magnétisme et de Spectroscopie des Solides LMSS, Université de Badji Mokhtar, Sidi Amar, Annaba 23220, Algerie.
⁶ Department of Electrical and Computer Engineering, University of California, Davis, CA 95616, USA.

Abstract

Undoped as well as (Co, Mn) co-doped Zinc oxides have been effectively developed on glass substrates, taking advantage of the spray pyrolysis procedure. The X-ray diffraction XRD as well as X-ray photoelectron spectroscopy (XPS) measurements have recognized a pure hexagonal wurtzite form of ZnO, and no other collateral phases such as MnO₂ or CoO₂ have been observed as a result of doping. The calculated values of the texture coefficient (TC) were between 0.15 and 5.14, indicating a dominant orientation along the (002) plane. The crystallite size (D) varies with the (Co, Mn) contents. The dislocation density (δ) as well as the residual microstrains increased after Co and Mn doping. Furthermore, the surface morphology of the films has been affected significantly by the Co and Mn incorporation, as shown by the scanning electron microscopy (SEM) investigation. The study of the optical properties exhibits a red shift of the band gap energy (E_g) with the (Co, Mn) co-doping. The magnetic measurements have shown that the undoped and (Co, Mn) co-doped ZnO thin films displayed room-temperature ferromagnetism (RTFM).

Keywords: SEM; XRD; diluted magnetic semiconductor; nanocrystallites; optical properties; room temperature ferromagnetism.