승화법에 의한 6H-SiC 단결정 성장 : (I) 성장결함생성기구

6H-SiC single crystal growth by the sublimation method : (I) the formation mechanism of growth defects

승화법에 의한 단결정 성장장치를 자체 제작하여 직경 약 30 mm, 길이 약 10 mm의 6H-Sic 단결정을 성장하였다. 최적의 성장조건은 원료온도 $2150~2250^{\circ}C$, 기판온도 $1950~2050^{\circ}C$, 원료부와 기판과의 온도차 약 $200^{\circ}C$, 성장압력 50~200 torr이었고, 성장속도는 300~700 $\mu\textrm{m}$/hr이었다. 성장된 결정의 표면을 광학현미경으로 관찰하여 성장결함 생성기구를 현상학적으로 고찰하였고, 특히 표면에서 관찰되는 micropipes의 생성원인을 규명하였다.

The 6H-SiC single crystals were grown using a self-designed crystal grower by the sublimation method. The grown crystals were typically 30 mm in diameter and 10 mm in length. Optimum growth conditions were established as follows : the temperature of the raw material was $2150~2250^{\circ}C$, the temperature of the substrate was $1950~2050^{\circ}C$, the temperature difference between the raw material and substrate was about $200^{\circ}C$, growth pressure was 50~200 torr and growth rate was 300~700 $\mu\textrm{m}$/hr. Optical microscopy was used for observing the surface of the 6H-SiC single crystal grown and the phenomenological approach was performed on the formation mechanism of the defects in the 6H-SiC crystal. Especially, the micropipes in the as-grown surface were examined to determine the formation mechanisms of the micropipes.