Discrimination of dislocations in 4H-SiC by inclination angles of molten-alkali etched pits  

作　　者：Guang Yang Hao Luo Jiajun Li Qinqin Shao Yazhe Wang Ruzhong Zhu Xi Zhang Lihui Song Yiqiang Zhang Lingbo Xu Can Cui Xiaodong Pi Deren Yang Rong Wang 

机构地区：[1]Key Laboratory of Optical Field Manipulation of Zhejiang Province,Department of Physics,Zhejiang Sci-Tech University,Hangzhou 310018,China [2]State Key Laboratory of Silicon Materials and School of Materials Science and Engineering,Zhejiang University,Hangzhou 310027,China [3]Hangzhou Innovation Center,Zhejiang University,Hangzhou 311200,China [4]School of Materials Science and Engineering&Henan Institute of Advanced Technology,Zhengzhou University,Zhengzhou 450001,China

出　　处：《Journal of Semiconductors》2022年第12期72-78,共7页半导体学报（英文版）

基　　金：supported by“Pioneer”and“Leading Goose”R&D Program of Zhejiang(Grant No.2022C01021);National Key Research and Development Program of China(Grant Nos.2018YFB2200101);Natural Science Foundation of China(Grant Nos.61774133);Fundamental Research Funds for the Central Universities(Grant No.2018XZZX003-02);Natural Science Foundation of China for Innovative Research Groups(Grant No.61721005);Zhejiang University Education Foundation Global Partnership Fund.

摘　　要：Discrimination of dislocations is critical to the statistics of dislocation densities in 4H silicon carbide(4H-SiC),which are routinely used to evaluate the quality of 4H-SiC single crystals and homoepitaxial layers.In this work,we show that the inclination angles of the etch pits of molten-alkali etched 4H-SiC can be adopted to discriminate threading screw dislocations(TSDs),threading edge dislocations(TEDs)and basal plane dislocations(BPDs)in 4H-SiC.In n-type 4H-SiC,the inclination angles of the etch pits of TSDs,TEDs and BPDs in molten-alkali etched 4H-SiC are in the ranges of 27°−35°,8°−15°and 2°−4°,respectively.In semi-insulating 4H-SiC,the inclination angles of the etch pits of TSDs and TEDs are in the ranges of 31°−34°and 21°−24°,respectively.The inclination angles of dislocation-related etch pits are independent of the etching duration,which facilitates the discrimination and statistic of dislocations in 4H-SiC.More significantly,the inclination angle of a threading mixed dislocations(TMDs)is found to consist of characteristic angles of both TEDs and TSDs.This enables to distinguish TMDs from TSDs in 4H-SiC.

关 键 词：4H-SiC single crystals dislocations molten-alkali etching 

分 类 号：TQ163.4[化学工程—高温制品工业]