公开(公告)号：US20240142390A1

公开(公告)日：2024-05-02

申请号：US18280825

申请日：2022-02-25

申请人： SHIN-ETSU HANDOTAI CO., LTD.

发明人： Yutaka SHIGA ,  Toru TAKAHASHI ,  Hisao MURAKI

IPC分类号： G01N21/95 ,  C30B29/36 ,  C30B33/10 ,  H01L21/66

CPC分类号： G01N21/9505 ,  C30B29/36 ,  C30B33/10 ,  H01L22/12

摘要： A method for evaluating crystal defects in a silicon carbide single crystal wafer, the method including steps of: etching a silicon carbide single crystal wafer with melted KOH so that a size of an etch pit due to a threading edge dislocation is 10 to 50 μm; obtaining microscopic images by automatic photographing at a plurality of positions on a surface of the silicon carbide single crystal wafer after the etching; determining presence or absence of a defect dense part in each of all the obtained microscopic images based on a continued length of the etch pit formed by the etching; and classifying all the obtained microscopic images into microscopic images having the defect dense part and microscopic images not having the defect dense part to evaluate a dense state of crystal defects in the silicon carbide single crystal wafer.