Comment on the paper “Contribution to the stability analysis of the dewetted Bridgman growth under microgravity conditions”

Abstract

New considerations of the stability problem of dewetting, as addressed in the initial paper [Cryst. Res. Technol. 39, 491 (2004)], show that, in the most general case, when dewetting occurs in microgravity it is necessarily stable. This explains why the phenomenon has been observed so many times during solidification of semiconductors in space.

Simultaneous X-ray radiography and diffraction topography imaging applied to silicon for defect analysis during melting and crystallization

“…Considering what was also observed in previous work during the solidification of single-crystal seeded samples (Tsoutsouva et al, 2016;Riberi-Bé ridot et al, 2015), new grains always nucleate with a AE3{111} twin relationship. Nucleation of twins preferentially occurs at the sample boundaries on {111} facets, because AE3 twinning on {111} planes is very common for silicon as it is associated with a very low surface energy (Duffar, 2010).…”

The grain–grain–liquid triple phase line during solidification of multi-crystalline silicon

“…It is therefore important to know how the grain structure develops in Si multi-crystalline ingots. This topic has been studied for a long time (see a review in [4]) and the multi-silicon structure is typically composed of three types of grains: See plots in [21,22] a Ref. [23] r e p o r t st h a ta n i s o t r o p yi sl e s st h a n1 5%i nt h eo r d e r{111} < {110} < {100}.…”

Experimental investigation of dewetting models

“…Stability analyses, generally based on Lyapunov's approach [17], have been performed for the three models. Simple approaches considering only the capillary effect [9,10] as well as more thorough analyses taking into account coupling between capillarity, heat transfer and pressure fluctuations [18][19][20][21][22][23] give the same result: dewetting is stable only when the meniscus is convex at the liquid-crystal-gas triple line, which means that abnormally high values of y should be considered in order to fulfil relation (1). In the case of model 3, stability also depends on the transport of gas dissolved in the liquid [21].…”