利用光学显微镜的反射模式观察了升华法生长的 6H SiC单晶 (0 0 0 1)Si 面的生长形貌 ,应用台阶仪测定了生长台阶高度。实验发现 ,6H SiC单晶的生长台阶呈螺旋状 ,生长台阶呈现出了韵律束合现象。在单晶中间部分 ,生长台阶稀疏 ,台面较宽 ,约 80 μm左右 ,台阶高度较小 ,约 2 0～ 5 0nm ,比较宽的台面上存在小生长螺旋。外围单晶区域 ,生长台阶比较密集 ,其台阶高度较大 ,约 30 0～ 70 0nm ,台面宽度较小 ,约 2～ 5 μm。生长台阶在前进过程中受单晶中的微管缺陷影响 ,在微管的附近出现弯曲 The growth morphology of 6H SiC single crystal (0 0 0 1) Si surface grown by sublimation method was observed by the reflection mode of optical microscope. The height of the growth step was measured by using the step analyzer. The experimental results show that the growth of 6H SiC single crystal is helical, and the growth step presents a rhythmic binding phenomenon. In the middle part of the single crystal, the growth step is sparse, the surface is wide, about 80 μm, the height of the step is small, about 20 ~ 50 nm, and the small growth spiral exists on the relatively wide mesa. In the peripheral single crystal region, the growth step is relatively dense, and the step height is large, about 30 0 ~ 70 0 nm, and the width of the mesa is small, about 2~5 μm. The growth step is affected by the defects of the microtubes in the single crystal during the advancing process, and the bending occurs near the microtubes