Effect of annealing on structural, optical, and electrical properties of nickel (Ni)/indium tin oxide (ITO) nanostructures prepared by RF magnetron sputtering

• Successfully deposited nickel/indium tin oxide (Ni/ITO) nanostructure on silicon (1 1 1) and glass substrate using RF magnetron sputtering.
• The growth temperature of ITO needs to exceed 200 °C to get a better crystallinity.
• Nickel acts as a catalyst during the deposition of ITO.
• Increasing the annealing temperature will increase the grain size and carrier concentration of Ni/ITO nanostructures.
• The lowest resistivity which is 1.09 × 10−6 Ω cm was achieved at 650 °C of annealing temperature.

Nickel (Ni)/indium tin oxide (ITO) nanostructures were deposited on glass and silicon (1 1 1) substrates by RF magnetron sputtering using nickel and ITO (In–Sn, 90–10%) targets. The post-deposition annealing has been performed for Ni/ITO films in air. The effect of annealing temperature on the electrical, optical and structural properties of ITO films was studied. We found the appearance of (6 2 2) peak in addition to (4 0 0) and (2 2 2) major peaks, which indicates an enhancement of the film crystallinity at high temperature annealing of 650 °C. The samples show higher transmittance of more than 90% at 470 nm after annealing which is suitable for blue light emitting diode (LED) application. The optical energy bandgap is shifted from 3.51 to 3.65 eV for the Ni/ITO film after annealing at 650 °C. In addition, increasing the annealing temperature improves the film electrical properties. The resistivity value decreases from 3.77 × 10−5 Ω cm to 1.09 × 10−6 Ω cm upon increasing annealing temperature.