Journal of Crystal Growth, Vol.401, 720-726, 2014
Effects of crucible coating on the quality of multicrystalline silicon grown by a Bridgman technique
A small diameter Bridgman equipment was used to investigate the influence of two crucible materials (fused silica and graphite) and two coatings materials (Si3N4 and CaCl2) on the quality of the multicrystalline silicon ingots, with focus on the ingot detachment from crucible, grain size and orientation and precipitate formation. It was shown that using a CaCl2 encapsulating substance can lead to grains larger in size and more oriented along the axial growth direction for both the graphite and the fused silica crucible, although the detachment of the crystal from the crucible is only possible if a fused silica crucible was used. The layer of the SiC precipitates at the graphite crucible wall was found to be thinner if the CaCl2 encapsulant was used. (C) 2014 Elsevier B.V. All rights reserved.