Effect of Solution Components on Solvent Inclusion in SiC Solution Growth

Abstract

In the solution growth method of silicon carbide, cellular structures and solvent inclusions are fatal defects. This study investigates the mechanism of how cosolvent chromium and additive aluminum influence the formation of cellular structures and inclusions via numerical simulations based on a phase field model. The simulation results indicate that introducing chromium into the solution increases the growth rate of the SiC crystals. The uneven distribution of chromium components near the macrostep edge is prone to trigger constitutional supersaturation, ultimately leading to cellular structures and inclusions. Constitutional supersaturation is more pronounced in solutions with a higher viscosity. Additionally, a small amount of additive aluminum increases the interfacial energy, enhancing the step stability by raising the potential barrier for curved steps and moderating step slopes. Experimental results demonstrate that a solution containing 40% chromium can increase the growth rate by three times compared to a pure Si solution. The Si 0.59 -Cr 0.4 -Al 0.01 solution emerges as a promising candidate, maintaining a high growth rate while preserving step stability and effectively suppressing the development of cellular structures and inclusions.

Wafer-Scale p-Type SiC Single Crystals with High Crystalline Quality

“…However, defects in SiC grown via the HTSG technique remain largely unexplored because the HTSG technique has been stagnant for many years. The reported defects in SiC grown from high-temperature solutions are cellular structures, solvent inclusions, apart from the thread edge dislocations, thread screw dislocations, and BPDs. ,− Thus, an in-depth identification of novel defects in SiC grown by TSSG is imperative to suppress or even eliminate defects for further optimization of material properties, contributing substantially to the performances of SiC-based devices.…”