FORMATION OF POLYCRYSTALLINE SILICON SHEET BY CAST RIBBON METHOD

摘要

PURPOSE:To prevent the breakage of a solidified silicon sheet by an initial tension through a cast ribbon method by which a melted silicon pressed into a mold nozzle by the use of a pulling jig is continuously pulled out as the solidi fied silicon sheet. CONSTITUTION:The bottom surface 10a of the casting passage 11 of a mold nozzle 5 is formed of the upper surface of a slidable susceptor 10. Melted silicon Si poured into the casting passage 11 is partially solidified and pulled out by the use of a pulling jig 7. In the initial pulling stage, the solidified silicon sheet MSi is pulled out together with the susceptor 10 only in a prescribed length L to reduce the static frictional force of the casting passage 11. The susceptor 10 is subsequently stopped and only the solidified silicon sheet MSi is pulled out against a small dynamic frictional force. The susceptor 10 is then returned to the original position and used for the next production step.