Synthesis and characterization of NiO-doped p-type AZO films fabricated by sol-gel method

► NiO doped p-type AZO films was first prepared by sol-gel method. ► NiO:AZO films showed a polycrystalline Ni2O3 (202) phase. ► p-type conductivity achieved by annealing in N2/H2forming gas at 550 °C. ► p-n junction (ITO/NiO:AZO) revealed rectifying I-V characteristics. ► The mean optical transmittance of NiO:AZO films >80 %.