Dislocation generation at near-coincidence site lattice grain boundaries during silicon directional solidification

• Published in: Journal of crystal growth Vol. 411; pp. 12 - 18
• Main Authors: Autruffe, Antoine, Stenhjem Hagen, Vegard, Arnberg, Lars, Di Sabatino, Marisa
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2015
• Subjects: A1. Defects; A1. Solidification; A2. Seeded growth; B1. Multicrystalline silicon; Defects; Deviation; Dislocations; Grain boundaries; Lattices; Low energy; Pollution sources; Seeds; Silicon; A1. Solidification; B1. Multicrystalline silicon; A1. Defects; A2. Seeded growth
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/j.jcrysgro.2014.10.054

Bi-crystal silicon ingots separated by near-coincident site lattice (near-CSL) grain boundaries (GBs), namely Σ9 and Σ27a, have been grown in a small scale Bridgman-type furnace at 3µm/s. Surface observations show different microstructure developments, depending on the nature of the seed GB and initial deviation from the low energy configuration. Grain boundary structure evolution and dislocation emission sources have been assessed for both types of GBs. Topological imperfections forming at the near – Σ9 and Σ27 GBs during the growth have been found to be the major source of defect generation. These imperfections are the result of the re-arrangement of the GBs during the growth due to the seed GBs deviation from low energy configurations – i.e. Σ9{221}1/{221}2 and Σ27a{511}1/{511}2. •Silicon bi-crystals separated by near-CSL grain boundaries were grown.•Unilateral lattice dislocation emissions were observed, correlating with larger strain field.•Their origin is discussed by the means of surface observations and EBSD.•The seed GB initial deviation from the low energy configuration results in the grown GB rearrangement.•This rearrangement is closely related to lattice dislocation emission.