Photoelectric properties of ITO thin films deposited by DC magnetron sputtering

Abstract

As anti-reflecting thin films and transparent electrodes of solar cells, indium tin oxide (ITO) thin films were prepared on glass substrates by DC magnetron sputtering process. The main sputtering conditions were sputtering power, substrate temperature and work pressure. The influence of the above sputtering conditions on the transmittance and conductivity of the deposited ITO films was investigated. The experimental results show that, the transmittance and the resistivity decrease as the sputtering power increases from 30 to 90 W. When the substrate temperature increases from 25 to 150 °C, the transmittance increases slightly whereas the resistivity decreases. As the work pressure increases from 0.4 to 2.0 Pa, the transmittance decreases and the resistivity increases. When the sputtering power, substrate temperature and work pressure are 30 W, 150 °C, 0.4 Pa respectively, the ITO thin films exhibit good electrical and optical properties, with resistivity below 10−4 Ω·cm and the transmittance in the visible wave band beyond 80%. Therefore, the ITO thin films are suitable as transparent electrodes of solar cells.