Analysis of grain orientation in cold crucible continuous casting of photovoltaic Si

✍ Scribed by B. Gallien; Th. Duffar; S. Lay; F. Robaut

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 589 KB
• Volume: 318
• Category: Article
• ISSN: 0022-0248
• DOI: 10.1016/j.jcrysgro.2010.10.100

✦ Synopsis

Grain orientation in multi-crystalline photovoltaic silicon is analyzed in the case of a square shaped ingot produced by cold crucible continuous casting (4C). This technique leads to a specific grain structure: horizontal on the wall where nucleation occurs and vertical at the center of the ingot. EBSD analysis along a solidification path shows that successive S3 twinning is the predominant source of variation in grain orientation. In fact, depending on the location along the solidification path, only 15-35% of grain boundaries are random boundaries without S3 n twinning relationship (1 r n r 5) and 34-48% are S3

twins. The grain orientation distribution is similar at the beginning and end of solidification, and the number of low angle grain boundaries is negligible.