基于三氯硅烷的高质量4H-SiC多片外延生长  

High Quality 4H-SiC Multi-Wafer Homoepitaxy Using TCS

作　　者：卜爱民 房玉龙[1] 李佳[1] 芦伟立[1] 赵丽霞[2] 杨龙 尹甲运[1] 刘沛 冯志红[1] 陈秉克[2] 蔡树军[1] 

机构地区：[1]专用集成电路国家级重点实验室,石家庄050051 [2]河北普兴电子科技股份有限公司,石家庄050200 [3]中国航天科技集团公司标准化研究院,北京100071

出　　处：《半导体技术》2018年第3期228-232,共5页Semiconductor Technology

摘　　要：使用三氯硅烷（TCS）作为含氯生长源,在多片外延设备生长了高质量的4H-SiC外延材料。研究了原位预刻蚀气体HCl流量和刻蚀时间对SiC外延材料表面三角形缺陷的影响,使用光学显微镜和表面缺陷分析仪对SiC外延材料表面缺陷进行表征测试和统计,使用傅里叶红外测试仪（FTIR）和原子力显微镜（AFM）对外延材料表面形貌进行表征。结果表明,预刻蚀气体体积流量和时间对4英寸SiC外延材料表面三角形缺陷影响明显,随着HCl体积流量和时间的增加,材料表面的三角形缺陷密度先减小后增加,在HCl流量为100 m L/min、刻蚀时间为20 min时,三角形缺陷密度最低达到0.47cm-2。此外,通过调整C/Si比和载气体积流量等参数,使4英寸SiC外延材料掺杂浓度不均匀性和厚度不均匀性均得到有效改善,结果表明该外延片质量满足SiC电力电子器件的应用。4H-SiC epitaxial material was grown on the commercial multi-wafer reactor using trichlorosilane （TCS） as the precursor. The influences of pre-etching HCl flow and pre-etching duration in situ on the triangular defects of SiC epilayers were systematically investigated. Surface defects of SiC epitaxial material were characterized and statistically analyzed by the optical microscope and morphological defects analyzer. The surface morphologies of the epitaxial matrial were characterized by Fourier transform infared spectroscopy （FTIR） and atomic force microscope （AFM）. The results show that pre-etching HCl flow and duration greatly affect the triangular defects density of the 4 inch SiC epilayers surface. As the HCl volume flow and time increase,the triangular defects density of epitaxial materials surface increases at first and then decreases. The lowest triangular defects density of 0.47 cm-2 was achieved with a pre-etching HCl flow of 100 m L/min and duration of 20 min. In addition,the doping concentration and thickness non uniformities of the 4 inch SiC epilayers were improved by adjusting the C/Si ratio and carrier gas flow. The results indicate that the quality of epitaxial layers grown in the planetary reactor can satisfy the SiC device applications.

关 键 词：SIC 外延 三氯硅烷(TCS) 缺陷 不均匀性 

分 类 号：TN304.054[电子电信—物理电子学] TN304.24