Growth of ZnO Thin Film for Solar Cell Electrode Deposited by Asymmetric Bipolar of DC Magnetron Sputtering Technique

Abstract

ZnO thin film for solar cell electrode deposited by asymmetric bipolar of DC magnetron sputtering technique. The ZnO thin film were prepared by asymmetric bipolar of DC magnetron sputtering technique which the negative electric potential of 480 V, the positive electric potential of 100 V, the current of 80 mA under Ar gas atmosphere at room temperature. ZnO thin films were grown by the deposition time of 10, 20, 30, 40 and 50 minutes, respectively. Moreover, growth of ZnO thin film the deposition time for 30 minutes was doped by N₂ gas the flow rate of 5, 10 and 15 sccm, respectively. Structural, morphological, optical and electrical properties of ZnO thin film were analyzed by X-Ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM), UV-vis spectrophotometer, Linear four-point probe and Hall effect measurement. The results found that, structural properties of thin films found that has high crystal and ZnO crystalline size of 16 nm at 002 plane on 2hteta of 34.34° for film coated under N₂ gas the flow rate of 5 sccm. Surface characteristic of film show a high crystal and the average grain sizes are approximately of 264 – 358 nm. ZnO thin films are in range of 67% - 83% and 55% - 77% for the film growth under a without N₂ gas and a doped N₂ gas. The resistivity values of ZnO thin films are 6.99x10², 5.55x10⁴, 2.26x10⁴ and 6.21x10⁴ Ω.m. Addition, the carrier concentration (n) are 1.61x10¹⁴ - 1.16x10¹⁸ cm^-3 which found that the carrier concentration somewhat highly and behaviors n-type semiconductor-like.  Thus, ZnO thin film deposited non-doped N₂ gas which the suitable for application to fabrication of transparent electrode for solar cell windows layer.