Substrate temperature effect on the SiC passivation layer synthesized by an RF magnetron sputtering method

This paper describes amorphous silicon carbide (a-SIC) film as an alternative material to silicon nitride (SIN) and silicon oxide (SiO2) for the passivation layer of solar cells. We deposited the film on p-type silicon (100) wafers and glass substrates by RF magnetron sputtering using a SIC (99%) target. Structural and optical properties of the films were investigated according to the process temperature (room temperature, 300 degrees C, 400 degrees C, 500 degrees C and 600 degrees C). The structural properties were analyzed by Raman microscopy and XPS (X-ray Photoelectron Spectroscopy). The XPS showed that the content of SIC in the film is increased when the substrate temperature is higher. The optical properties of the films were examined by UV-visible spectroscopy and Ellipsometer. The optical characteristic measurement showed that the lowest refractive index of the film is 2.65. Also, using carrier lifetime measurement, we investigated the performance of SiC as the passivation layer. At the substrate temperature of 600 degrees C, we obtained a highest carrier lifetime of 7.5 mu s. (C) 2011 Elsevier B.V. All rights reserved.