Publica
Hier finden Sie wissenschaftliche Publikationen aus den FraunhoferInstituten. A quantitative model with new scaling for silicon carbide particle engulfment during silicon crystal growth
 Journal of Crystal Growth 463 (2017), S.100109 ISSN: 00220248 
 Bundesministerium für Wirtschaft und Technologie BMWi 50WM1147 

 Englisch 
 Zeitschriftenaufsatz 
 Fraunhofer IISB () 
Abstract
We present rigorous numerical modeling and analytical arguments to describe data on the engulfment of silicon carbide particles during silicon crystal growth obtained via advanced terrestrial and microgravity experiments. For the first time in over a decade of research on SiC inclusions in silicon, our model is able to provide a quantitative correlation with experimental results, and we are able to unambiguously identify the underlying physical mechanisms that give rise to the observed behavior of this system. In particular, we identify a significant and previously unascertained interaction between particleinduced interface deflection (originating from the thermal conductivity of the SiC particle being larger than that of the surrounding silicon liquid) and curvatureinduced changes in melting temperature arising from the GibbsThomson effect. For a particular range of particle sizes, the GibbsThomson effect flattens the deflected solidification interface, thereby reducing drag on the particle and increasing its critical velocity for engulfment. We show via numerical calculations and analytical reasoning that these effects give rise to a new scaling of the critical velocity to particle size as v(c) similar to (5/3), whereas all prior models have predicted either v(c) similar to R1 or v(c) similar to R4/3. This new scaling is needed to quantitatively describe the experimental observations for this system.