超高压4H-SiC p-IGBT器件材料CVD外延生长

Epitaxial Growth of 4H-SiC for Ultra High Voltage p-IGBT Power Devices

介绍偏晶向4H-SiC衬底上化学气相沉积(CVD)外延生长及其竞位掺杂方法,使用"热壁"CVD外延生长系统,在4英寸4°偏角n^+型4H-SiC衬底上进行了p型4H-SiC外延层及p型绝缘栅双极型晶体管(p-IGBT)器件用p^-n^+结构材料生长,利用Candela CS920表征了100μm厚p型4H-SiC外延层表面缺陷及结构缺陷,典型表面缺陷为三角形缺陷和胡萝卜缺陷,3种结构缺陷分别是基晶面位错(BPD)、三角形肖克利型层错(SSF)和条形层错(BSF)。微波光电导衰退法(μ-PCD)测试表明,100μm厚p型4H-SiC外延层载流子寿命为2.29μs,采用二次离子质谱(SIMS)测试方法分析了不同铝(Al)掺杂浓度的深度分布,最高Al掺杂浓度为2×10^(19)cm^(-3)。

The chemical vapor deposition （CVD） epitaxial growth and site competition epitaxy of 4H-SiC on 4 inches 4° off-cut substrates is introduced and the results of p-type 4H-SiC epilayers and p^-n^＋ structure materials for 10 kV- class p-IGBT devices are reported.Both surface defects,like triangles and carrots,and crystallographic defects,like basal plane dislocation （BPD）, Shockley stacking fault （SSF） and bar stacking fault （BSF）, are characterized by Can- dela CS920.The average microwave photoconductivity decay（μ-PCD） lifetime of 100 μm thick p-type 4H-SiC epilayer is 2.29 μs.Different doping density of depth distribution is analyzed by secondary ion mass spectroscopy （SIMS）, the heavily doped Al concentration is 2×10^19cm^-3.