Modeling and Suppressing Interfacial Instability in Growth of SiC from High-Temperature Solutions

Interfacial instability is often encountered in the growth of silicon carbide (SiC) via a high-temperature solution technique, severely deteriorating the crystalline quality or leading to growth failure. Here, we develop a model describing the variation of carbon concentration in the vicinity of the interface between the crystal surface and solution during the stable growth process. A critical condition under which the interfacial instability occurs is derived, which is different from that based on the classical constitutional undercooling. It indicates that slow growth rate, low temperature gradient, high diffusion coefficient of carbon, and short melt height are conducive to eliminate the interfacial instability. The validity is verified by changing these key growth parameters to avoid the grooves and melt traps in growing 4 in. 3C–SiC from melts. The results should be applicable to grow other polytypes of SiC crystals by a high-temperature solution technique.