公开(公告)号：US11114295B2

公开(公告)日：2021-09-07

申请号：US16901435

申请日：2020-06-15

Applicant: SHOWA DENKO K.K.

Inventor： Takashi Aigo ,  Wataru Ito ,  Tatsuo Fujimoto

IPC: H01L21/02 ,  C30B25/16 ,  C30B29/36 ,  H01L21/205 ,  C23C16/32 ,  C30B25/18 ,  C30B25/20 ,  C23C16/02 ,  C23C16/455 ,  C30B29/06

Abstract: An epitaxial silicon carbide single crystal wafer having a small depth of shallow pits and having a high quality silicon carbide single crystal thin film and a method for producing the same are provided. The epitaxial silicon carbide single crystal wafer according to the present invention is produced by forming a buffer layer made of a silicon carbide epitaxial film having a thickness of 1 μm or more and 10 μm or less by adjusting the ratio of the number of carbon to that of silicon (C/Si ratio) contained in a silicon-based and carbon-based material gas to 0.5 or more and 1.0 or less, and then by forming a drift layer made of a silicon carbide epitaxial film at a growth rate of 15 μm or more and 100 μm or less per hour. According to the present invention, the depth of the shallow pits observed on the surface of the drift layer can be set at 30 nm or less.

公开(公告)号：US10450672B2

公开(公告)日：2019-10-22

申请号：US15323655

申请日：2015-07-16

Applicant: SHOWA DENKO K.K.

Inventor： Takashi Aigo ,  Wataru Ito ,  Tatsuo Fujimoto

IPC: C30B25/18 ,  C30B25/14 ,  C30B29/36 ,  H01L21/20 ,  H01L21/205 ,  C30B25/16 ,  C30B25/20

Abstract: The object is to produce with good reproducibility an epitaxial silicon carbide wafer having a high quality silicon carbide single crystal thin film with little step bunching. To achieve this object, for etching the silicon carbide single crystal substrate in the epitaxial growth furnace, hydrogen carrier gas and silicon-based material gas are used. After the etching treatment is finished as well, the epitaxial growth conditions are changed in the state in the state supplying these gases. When the conditions stabilize, a carbon-based material gas is introduced for epitaxial growth.

公开(公告)号：US10727047B2

公开(公告)日：2020-07-28

申请号：US15544697

申请日：2016-02-16

Applicant: SHOWA DENKO K.K.

Inventor： Takashi Aigo ,  Wataru Ito ,  Tatsuo Fujimoto

IPC: H01L21/02 ,  C30B25/16 ,  C30B29/36 ,  H01L21/205 ,  C23C16/32 ,  C30B25/18 ,  C30B25/20 ,  C23C16/02 ,  C23C16/455 ,  C30B29/06

Abstract: An epitaxial silicon carbide single crystal wafer and a method for producing the same, wherein the epitaxial silicon carbide single crystal wafer is produced by forming a buffer layer made of a silicon carbide epitaxial film having a thickness of 1 μm or more and 10 μm or less by adjusting the ratio of the number of carbon to that of silicon (C/Si ratio) contained in a silicon-based and carbon-based material gas to 0.5 or more and 1.0 or less, and then by forming a drift layer made of a silicon carbide epitaxial film at a growth rate of 15 μm or more and 100 μm or less per hour, thereby bringing a depth of shallow pits observed on the surface of the drift layer to 30 nm or less.

公开(公告)号：US10435813B2

公开(公告)日：2019-10-08

申请号：US15548217

申请日：2016-02-12

Applicant: SHOWA DENKO K.K.

Inventor： Wataru Ito ,  Takashi Aigo ,  Tatsuo Fujimoto

IPC: C30B25/20 ,  C30B25/14 ,  C23C16/42 ,  C23C16/452 ,  C30B29/36 ,  H01L21/205 ,  C30B25/16 ,  C23C16/32 ,  H01L21/02

Abstract: The present invention provides a method of epitaxial growth of an SiC thin film by the thermal CVD process wherein it is possible to improve the in-plane uniformity of the doping density and possible to grow an SiC thin film by a uniform thickness. This method is an epitaxial growth method for silicon carbide characterized by comprising adjusting a ratio of the hydrocarbon gas and silicon feedstock gas so as to become, by C/Si ratio, 0.5 to 1.5 in range, making the hydrocarbon gas contact a hydrocarbon decomposition catalyst heated to 1000° C. to 1200° C. so as to make at least part of the hydrocarbon gas break down into carbon and hydrogen, and supplying carbon contained in the hydrocarbon gas and silicon contained in the silicon feedstock gas to the silicon carbide single crystal substrate.

公开(公告)号：US20200312656A1

公开(公告)日：2020-10-01

申请号：US16901435

申请日：2020-06-15

Applicant: SHOWA DENKO K.K.

Inventor： Takashi Aigo ,  Wataru Ito ,  Tatsuo Fujimoto

IPC: H01L21/02 ,  C30B25/16 ,  C30B29/36 ,  H01L21/205 ,  C23C16/32 ,  C30B25/18 ,  C30B25/20 ,  C23C16/02 ,  C23C16/455 ,  C30B29/06

Abstract: An epitaxial silicon carbide single crystal wafer having a small depth of shallow pits and having a high quality silicon carbide single crystal thin film and a method for producing the same are provided. The epitaxial silicon carbide single crystal wafer according to the present invention is produced by forming a buffer layer made of a silicon carbide epitaxial film having a thickness of 1 μm or more and 10 μm or less by adjusting the ratio of the number of carbon to that of silicon (C/Si ratio) contained in a silicon-based and carbon-based material gas to 0.5 or more and 1.0 or less, and then by forming a drift layer made of a silicon carbide epitaxial film at a growth rate of 15 μm or more and 100 μm or less per hour. According to the present invention, the depth of the shallow pits observed on the surface of the drift layer can be set at 30 nm or less.