A sessile drop approach for studying 4H-SiC/liquid silicon high-temperature interface reconstructions

Abstract

Accurate description, understanding and control of the high temperature interface behavior between the SiC single crystal and liquid phase is critical for further development of SiC solution growth. The different parameters which create morphological instabilities, such as step bunching, micro-faceting and solvent trapping, remain unclear because they are very difficult to address in high temperature experiments. We combined experiments and numerical simulation to design a specific sessile drop approach where the liquid is removed before cooling down. The advantage of this method that it activates or suppresses the solute (carbon) transport by an AC magnetic field and thus separates the physical–chemical and hydrodynamic contributions. The method was demonstrated through observation of the morphological evolution of a 4°off 4H-SiC (0001) surface in contact with pure liquid silicon at 1600 °C according to the time factor. Several parasitic effects were also analyzed and suppressed in order to obtain a well-controlled uniform interface.