GROWTH OF SILICON RIBBONS BY THE RAD PROCESS

This paper describes the RAD growth process which has been conceived in order to achieve silicon sheets for terrestrial photovoltaics. The growth of the ribbon, the preparation of unsupported silicon sheets and the material properties are successively presented. It is shown that the use of carbon substrate in this process permits the achievement of flat silicon sheets down to 50 µm in thickness at pull rates up to 10 cm/min. The structural and compositional characteristics of the layers are compatible with the achievement of relatively high values of the solar cell conversion efficiency, the best result being 15.5 % (AM1 illumination, anti-reflection coated cell).