Low Cost High Speed Si Ribbon Growth by the HSW-Technique

The development of the Horizontal Supported Web (HSW) technique for growth of Si ribbon material for solar cells has been continued. The dependence of the pulling speed on the melt length was calculated and the influence of the temperature gradient in the melt investigated. In present experiments a pulling speed of 1 m/min is used requiring a melt length of about 20 cm. At this speed the continuous growth of ribbons several meters long, 6 cm wide and 0.6 mm thick has been obtained. Test solar cells 2 cm x 2 cm in size have an efficiency of η = 11%. The cost per Watt-area were estimated for different production rates and conditions; at 6 MW/ a the cost comes down to 0.40 Dollar/Watt-area.