公开(公告)号：US11961736B2

公开(公告)日：2024-04-16

申请号：US17683176

申请日：2022-02-28

Applicant: SHOWA DENKO K.K.

Inventor： Ling Guo ,  Koji Kamei

IPC: C23C16/32 ,  C30B25/20 ,  C30B29/36 ,  G01N21/95 ,  G06T7/00 ,  H01L21/02 ,  H01L21/66 ,  H01L29/16 ,  H01L29/32

CPC classification number: H01L21/02378 ,  C23C16/325 ,  C30B25/20 ,  C30B29/36 ,  G01N21/9505 ,  G06T7/0004 ,  H01L21/02433 ,  H01L21/02529 ,  H01L21/0259 ,  H01L21/0262 ,  H01L21/02634 ,  H01L22/12 ,  H01L29/1608 ,  H01L29/32 ,  G06T2207/10056 ,  G06T2207/30148

Abstract: A SiC epitaxial wafer in which a SiC epitaxial layer is formed on a 4H-SiC single crystal substrate having an off angle and a substrate carbon inclusion density of 0.1 to 6.0 inclusions/cm2, wherein a total density of large pit defects and triangular defects caused by substrate carbon inclusions and contained in the SiC epitaxial layer is 0.01 defects/cm2 or more and 0.6 defects/cm2 or less. The large pit defect is a pit located on a surface at a position corresponding to a position of the carbon inclusion on the substrate surface, and a conversion rate from the substrate carbon inclusions to the large pit defects and the triangular defects caused by the substrate carbon inclusions is 20% or less. Also disclosed is a method for producing the SiC epitaxial wafer.

公开(公告)号：US11320388B2

公开(公告)日：2022-05-03

申请号：US16327445

申请日：2017-08-21

Applicant: SHOWA DENKO K.K.

Inventor： Ling Guo ,  Koji Kamei

IPC: C30B25/18 ,  G01N21/95 ,  C23C16/32 ,  C30B25/20 ,  C30B29/36

Abstract: A SiC epitaxial wafer in which a SiC epitaxial layer is formed on a 4H—SiC single crystal substrate having an off angle and a substrate carbon inclusion density of 0.1 to 6.0 inclusions/cm2, and wherein a density of large pit defects caused by substrate carbon inclusions and contained in the SiC epitaxial layer is 0.5 defects/cm2 or less.

公开(公告)号：US11293115B2

公开(公告)日：2022-04-05

申请号：US16325281

申请日：2017-08-21

Applicant: SHOWA DENKO K.K.

Inventor： Ling Guo ,  Koji Kamei

IPC: C30B25/18 ,  C30B29/36 ,  C30B25/20 ,  C23C16/32 ,  G01N21/95 ,  G06T7/00 ,  H01L29/16 ,  H01L21/02 ,  H01L21/66 ,  H01L29/32

Abstract: A SiC epitaxial wafer in which a SiC epitaxial layer is formed on a 4H-SiC single crystal substrate having an off angle and a substrate carbon inclusion density of 0.1 to 2.5 inclusions/cm2, wherein a total density of large pit defects and triangular defects caused by substrate carbon inclusions and contained in the SiC epitaxial layer is 0.6 defects/cm2 or less.

公开(公告)号：US12228523B2

公开(公告)日：2025-02-18

申请号：US17009130

申请日：2020-09-01

Applicant: SHOWA DENKO K.K.

Inventor： Ling Guo

IPC: G01N21/95 ,  C30B23/00 ,  C30B29/36 ,  G01N21/64 ,  H01L21/66 ,  H01L21/78

Abstract: This method of evaluating a SiC substrate includes a preparation step of preparing two or more SiC substrates obtained from the same SiC ingot grown from the same seed crystal, a defect position specifying step of specifying positions of defects in the substrates by observing a main surface of each of the two or more SiC substrates, and a comparison step of comparing the positions of the defects of the two or more SiC substrates, in which, in the preparation step, a SiC substrate positioned closest to the seed crystal is used as a reference wafer among the two or more SiC substrates, and the comparison step comprises a sub-step wherein a first defect of the reference wafer is compared with a second defect of a SiC substrate other than the reference wafer, it is judged whether a defect distance of the two compared defects in a [11-20] direction is 0.6 mm or more or less than 0.2 mm, and the two compared defects are determined to be defects not associated with the same threading defect when the defect distance is 0.6 mm or more, and the two compared defects are determined to be defects associated with the same threading defect when the defect distance is less than 0.2 mm.