Optical properties of aluminum-doped zinc oxide thin films for solar cell application

• Main Author: Heng, Shu Wei.
• Other Authors: Sam Zhang Shanyong
• Format: Final Year Project
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering::Mechanical engineering::Alternative, renewable energy sources; DRNTU::Engineering::Materials::Material testing and characterization
• Online Access: http://hdl.handle.net/10356/16852
• Institution: Nanyang Technological University

To date, great interests have been generated in research on renewable green energy such as fuel cells and solar cells. In photovoltaic cells, transparent conducting oxide layers are commonly used as the front contact layers. Due to the low cost and good optical and electrical properties, aluminum-doped zinc oxide (AZO) is a promising alternative to indium-tin oxide in view of solar cell application. In the current project, effect of different deposition parameters on the optical properties of aluminum-doped zinc oxide thin films was investigated. The AZO thin films were prepared onto glass substrate under different deposition conditions by magnetron sputtering. Parameters that were varied included RF power on the zinc oxide target, DC Power on the aluminum target, deposition pressure, and oxygen flow rate. The effect of wet etching on optical properties AZO thin films were performed using diluted hydrochloric acid. The properties of the aluminum-doped zinc oxide thin films were measured using scanning electron microscope, atomic force microscope, surface profiler and UV-vis spectrophotometer. Optical transmittance level of the AZO thin films presents a value of more than 80% in the current work. Wet etching of the aluminum-doped zinc oxide thin films results in an increase in both the surface roughness and light transmittance level.