Annealing effect on conductivity behavior of Li–doped ZnO thin film and its application as ZnO-based homojunction device

Abstract

Transparent electronics is an advanced technology concerning the realization of invisible electronic circuits. The p-type doping in ZnO wide band gap semiconductor has been a challenge for research for many years. In this work, Lithium-doped ZnO films were deposited by the RF magnetron sputtering method. The influence of post-annealing temperature on the electrical, structural and optical properties of ZnO:Li films were investigated. The results show that the ZnO:Li films show (0 0 2) preferred orientation and high average transmittance about 85% in the visible region after annealing temperature of about 550 °C. The optimal p-type conduction of ZnO:Li film is achieved at the post-annealing temperature of 450 °C with a resistivity of 0.22 Ω cm, hole carrier concentration of 2.47×10 18 cm −3 and mobility of 0.22 cm 2/V s. Finally, p–n homojunction based on transparent semiconducting oxides is fabricated.