Effect of Fe-incorporation on Structural and Optoelectronic Properties of Spin Coated p/n Type ZnO Thin Films

Authors C. Zegadi1 , M. Adnane2, D. Chaumont3, A. Haichour1 , A. Hadj kaddour4, Z. Lounis4, D. Ghaffor4

1Laboratoire de Micro et de Nanophysique (LaMiN), Ecole Nationale Polytechnique d’Oran Maurice AUDIN (ENPO-MA), BP 1523 El-Mnaouer, 31000 Oran, Algeria

2Laboratory of Electron Microscopy and Materials Sciences, University of Science and Technology of Oran, P.O. Box 1505, El-Mnaouer, 31000 Oran, Algeria

3Équipe NanoForm, Laboratoire ICB, Université de Bourgogne, 9, Ave Alain Savary, 21078 Dijon, France

4Laboratory of LABMAT, National Polytechnic School of Oran, ENP Oran- Maurice AUDIN, Oran, Algeria

Е-mail chawki.zegadi@enp-oran.dz
Issue Volume 12, Year 2020, Number 3
Dates Received 03 February 2020; revised manuscript received 15 June 2020; published online 25 June 2020
Citation C. Zegadi, M. Adnane, et al., J. Nano- Electron. Phys. 12 No 3, 03023 (2020)
DOI https://doi.org/10.21272/jnep.12(3).03023
PACS Number(s) 61.05.cp, 51.50. + v, 07.60.Rd
Keywords ZnO films, Fe-doping, X-ray pattern, UV-Vis spectra, Raman scattering (4) , p/n-type conductivity, XPS spectrum.

This paper reports the effect of Fe incorporation on structural and electro-optical properties of ZnO thin films prepared by spin coating techniques.The Fe/Zn nominal volume ratio was 7 % in the solution. X-ray diffraction patterns of the films showed that doped incorporation leads to substantial changes in the structural characteristics of ZnO films. All the films have polycrystalline structure, with a preferential growth along the ZnO (002) plane. The crystallite size was calculated using a well-known Scherrer’s formula and found to be in the range of 22-17 nm. The highest average optical transmittance value in the visible region was belonging to the Fe doped ZnO film. The results of the Raman scattering confirmed the observations of XRD and UV-Vis analysis techniques by the appearance of these occupancies at Zn+2 sites. These results are explained theoretically and are compared with those reported by other workers. The results of Hall measurement of ZnO and ZnO:Fe thin films reveal a high electron concentration around 1016 cm – 3 and low mobility 2.6 cm2/Vs. All as-grown samples show ambiguous carrier conductivity type (p-type and n-type) in the automatic Van der Pauw Hall measurement. A similar result has been observed in Li-doped ZnO and in As-doped ZnO films by other groups before. However, by characterizing our samples whit XPS, we have demonstrated that the ambiguous carrier type n in intended our ZnO films is not intrinsic behavior of the samples. It is due to the persistent photoconductivity effect in ZnO.

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