采用行星热壁式SiC外延炉对100 mm 4°偏轴4H-SiC衬底外延工艺进行了研究。分析了氢气预刻蚀工艺对4°偏轴衬底外延材料表面形貌的影响。采用双指标正交实验,通过极差分析的方法研究了C/Si比、Cl/Si比、主氢流量、生长温度、三路气体比等工艺参数对SiC外延厚度和掺杂浓度均匀性指标影响的主次顺序,并给出了优化的外延参数。采用该工艺条件制得的无台阶聚集形貌的SiC外延片片内厚度均匀性和浓度均匀性分别是1.23%和3.32%。 A 100 mm 4 ° off-axis 4H-SiC substrate epitaxial process was studied using a planetary thermal wall SiC epitaxial furnace. The effect of hydrogen pre-etching process on the surface morphology of 4 ° off-axis epitaxial substrate was analyzed. Using double index orthogonal experiment, the parameters of C / Si ratio, Cl / Si ratio, main hydrogen flow rate, growth temperature, gas ratio of three gas and so on were used to study the uniformity of SiC epitaxial thickness and doping concentration Affect the order of the primary and secondary, and give the optimal parameters of the extension. The thickness uniformity and density uniformity of the SiC epitaxial wafers without the step-like morphology obtained by this process were 1.23% and 3.32%, respectively.