Spontaneous nucleation of SiC particles and giant macroscopic steps result in the surface roughness of the grown crystal for the top-seeded solution growth of SiC crystal. To suppress the surface roughness, the temperature gradient was carefully adjusted by changing the relative position of the crucible and induction coils. The numerical simulation and experimental results show that the surface morphology of the grown crystal becomes smoother and there are fewer spontaneous nucleation particles attached to the growth surface with the decrease in the relative crucible position, due to the increase of temperature at the entire solution surface and the reducing of temperature gradient near the growth surface. Accordingly, a lower temperature gradient, a larger solution velocity, a higher carbon concentration, and a smaller carbon supersaturation near the growth surface can be obtained when the relative position between the crucible and the induction coil is 70 mm, which is demonstrated to be the most favorable for the elimination of spontaneous nucleation of small SiC particles and suppressing surface roughening with the full width at half maximum (FWHM) of 37.5 arcsec of 4H-SiC crystals.

中文翻译：

---

通过调整 SiC 晶体顶晶种固溶体生长中的温度分布来抑制表面粗糙度。


SiC 颗粒的自发成核和巨大的宏观台阶导致生长晶体的表面粗糙度，从而导致 SiC 晶体的顶晶固溶生长。为了抑制表面粗糙度，通过改变坩埚和感应线圈的相对位置来仔细调整温度梯度。数值模拟和实验结果表明，由于整个溶液表面温度的升高和生长表面附近温度梯度的减小，随着相对坩埚位置的减少，生长晶体的表面形貌变得更加光滑，附着在生长表面的自发成核颗粒减少。因此，当坩埚和感应线圈之间的相对位置为 70 mm 时，可以获得较低的温度梯度、较大的溶解速度、较高的碳浓度和较小的生长表面过饱和度，这被证明最有利于消除小 SiC 颗粒的自发成核和抑制表面粗糙化，半峰全宽 （FWHM） 为 37.5 arcsec的 4H-SiC 晶体。