Effect of sputtering power on the electrical and optical properties of Ca-doped ZnO thin films sputtered from nanopowders compacted target

H. Mahdhi (1) , Z. Ben Ayadi (1) , J.L. Gauffier (2) , K. Djessas (3) , S. Alaya (1)

1 Laboratoire de Physique des Matérieux et des Nanomatériaux appliquée à l'Environnement
2 Département de Génie Physique
3 PROMES - Procédés, Matériaux et Energie Solaire

In the present work, we have deposited calcium doped zinc oxide thin films by magnetron sputtering technique using nanocrystalline particles elaborated by sol–gel method as a target material. In the first step, the nanoparticles were synthesized by sol–gel method using supercritical drying in ethyl alcohol. The structural properties studied by X-ray diffractometry indicates that Ca doped ZnO has a polycrystalline hexagonal wurzite structure with a grain size of about 30 nm. Transmission electron microscopy (TEM) measurements have shown that the synthesized CZO is a nanosized powder. Then, thin films were deposited onto glass substrates by rf-magnetron sputtering at ambient temperature. The influence of RF sputtering power on structural, morphological, electrical, and optical properties were investigated. It has been found that all the films deposited were polycrystalline with a hexagonal wurtzite structure and preferentially oriented in the (0 0 2) crystallographic direction. They have a typical columnar structure and a very smooth surface. The as-deposited films show a high transmittance in the visible range over 85% and low electrical resistivity at room temperature.

Keywords: Thin films; Ca-doped ZnO; Sol–gel growth; Sputtering; Optical properties

Domains: Engineering Sciences [physics]

H. Mahdhi, Z. Ben Ayadi, J.L. Gauffier, K. Djessas, S. Alaya. Effect of sputtering power on the electrical and optical properties of Ca-doped ZnO thin films sputtered from nanopowders compacted target. Optical Materials, 2015, 45, pp.97-103. ⟨10.1016/j.optmat.2015.03.015⟩. ⟨hal-01176296⟩