利用课题组自主研发的热壁低压化学气相沉积(HWLPCVD)系统,在朝[11-20]方向偏转4°的(0001)Si面4H-SiC衬底上进行快速同质外延生长,研究了生长温度及氯硅比(Cl/Si比)对外延生长速率的影响机理。研究发现,外延生长速率随生长温度的提高呈线性增加,而Cl/Si比的改变对生长速率的影响不大。文章进一步探究了Cl/Si比对4H-SiC外延层表面缺陷的影响。较低的Cl/Si比(0.4~2)可以减少或消除三角缺陷,Cl/Si比较高(大于5)时,表面质量反而下降,因而,适当的Cl/Si比对于获得表面形貌良好的4H-SiC外延层至关重要。 Rapid thermal homoepitaxial growth was performed on a (0001) Si surface 4H-SiC substrate deflected 4 [11-20] by HWLPCVD system independently developed by our research group. Effect of temperature and ratio of chlorine to silicon (Cl / Si ratio) on epitaxial growth rate. The results show that the epitaxial growth rate increases linearly with the increase of growth temperature, while the change of Cl / Si ratio has little effect on the growth rate. The paper further explores the effect of Cl / Si ratio on the surface defects of 4H-SiC epitaxial layer. The lower Cl / Si ratio (0.4 ~ 2) can reduce or eliminate the triangular defects. When the Cl / Si ratio is higher (greater than 5), the surface quality decreases. Therefore, the suitable Cl / Si ratio is good for obtaining surface morphology 4H-SiC epitaxial layer is crucial.