Zn0.92Cu0.08O nanorods array were synthesized by radio frequency magnetron sputtering deposition at different substrate temperatures. No extra catalysts were used during synthesis. The structural and photoluminescence properties were investigated. Results showed that the ferromagnetism (FM) observed at 20 degrees C were an intrinsic property of Cu-doped ZnO nanorods. With the increase in substrate temperature, an improved crystallinity along with the increase in oxygen vacancies was observed in Zn0.92Cu0.08O nanorods, which caused an enhancement of magnetic moment in Zn0.92Cu0.08O nanorods. The experimental results showed that the interaction between substitutional Cuzn in a divalent charge and oxygen vacancies played an important role in the origin of ferromagnetism in Zn0.92Cu0.08O nanorods. The observed FM is explained in terms of the defect related mechanism. (C) 2013 Elsevier B.V. All rights reserved.