4H-SiC贯穿型位错及其密度分布的表征方法优化  

Optimization of Characterization Methods for 4H-SiC Threading Dislocation and Its Density Distribution

作　　者：章宇 陈诺夫[1,2] 张芳 余雯静[3] 胡文瑞 陈吉堃 Zhang Yu;Chen Nuofu;Zhang Fang;Yu Wenjing;Hu Wenrui;Chen Jikun(School of New Energy,North China Electric Power University,Beijing 102206,China;Yunnan Lincang Xinyuan Germanium Industry Co.,Ltd.,Academician Hu Wenrui Workstation,Lincang 677011,China;School of Light Industry,Beijing Technology and Business University,Beijing 100048,China;Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China;School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]华北电力大学新能源学院,北京102206 [2]胡文瑞院士工作站云南临沧鑫圆锗业股份有限公司,云南临沧677011 [3]北京工商大学轻工科学技术学院,北京100048 [4]中国科学院力学研究所,北京京100190 [5]北京科技大学材料科学与工程学院,北京100083

出　　处：《半导体技术》2023年第11期977-984,共8页Semiconductor Technology

基　　金：国家自然科学基金资助项目(52073090);国家重点研发计划项目(2021YFA0718901)。

摘　　要：目前用来揭示SiC的贯穿型位错缺陷的表征方法主要是湿法碱腐蚀,但现阶段利用KOH腐蚀4H-SiC晶片的腐蚀参数各不相同,腐蚀结果也有待优化。研究了熔融KOH对4H-SiC晶片的腐蚀形貌,利用金相显微镜和扫描电子显微镜(SEM)观测腐蚀晶片,发现4H-SiC晶片在500℃熔融KOH中腐蚀20 min效果为最优。在此基础上研究分析了半绝缘4H-SiC晶片的贯穿型位错的密度和分布。结果表明,半绝缘型SiC晶片中贯穿型位错密度的分布具有一定的规律性,呈现出从晶片中心区域向晶片边缘处增长的特性,而这可能源于在物理气相传输法下SiC单晶生长不同区域产生的热应力不同。Currently,the characterization method used to reveal the threading dislocation defects of SiC is mainly wet alkali etching.But the etching parameters of 4H-SiC wafers etched with potassium hydroxide(KOH)are different at this stage,and the etching results need to be optimized.The etching morphology of 4H-SiC wafers by molten KOH was investigated,and metallographic microscope and scanning electron microscope(SEM)were used to observe the etched wafers.It is found that the best etching effect for 4H-SiC wafer is at 500 in molten K0H for 20 min.On this basis,the density and distribution of threading dislocations in semi-insulated 4H-SiC wafers were explored and analyzed.The results indicate that the density distribution of threading dislocations in semi-insulated SiC wafers has certain regularity,showing the characteristics of increase from the central region to the edge of the wafer.This can be attributed to the different thermal stresses generated in different regions of SiC single crystal growth by physical vapor transport method.

关 键 词：SIC 湿法腐蚀 贯穿型位错 位错密度 位错缺陷分布 

分 类 号：TN304.24[电子电信—物理电子学] TN307