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公开(公告)号：US20230078982A1
公开(公告)日：2023-03-16
申请号：US17976191
申请日：2022-10-28
Applicant: SiCrystal GmbH
Inventor： Bernhard Ecker , Ralf Müller , Matthias Stockmeier , Michael Vogel , Arnd-Dietrich Weber
Abstract: The present invention relates to a chamfered silicon carbide substrate which is essentially monocrystalline, and to a corresponding method of chamfering a silicon carbide substrate. A silicon carbide substrate according to the invention comprises a main surface (102), wherein an orientation of said main surface (102) is such that a normal vector ({right arrow over (O)}) of the main surface (102) includes a tilt angle with a normal vector ({right arrow over (N)}) of a basal lattice plane (106) of the substrate, and a chamfered peripheral region (110), wherein a surface of the chamfered peripheral region includes a bevel angle with said main surface, wherein said bevel angle is chosen so that, in more than 75% of the peripheral region, normal vectors ({right arrow over (F)}_i) of the chamfered peripheral region (110) differ from the normal vector of the basal lattice plane by less than a difference between the normal vector of the main surface and the normal vector of the basal lattice plane of the substrate.
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公开(公告)号：US11515140B2
公开(公告)日：2022-11-29
申请号：US16409706
申请日：2019-05-10
Applicant: SiCrystal GmbH
Inventor： Bernhard Ecker , Ralf Müller , Matthias Stockmeier , Michael Vogel , Arnd-Dietrich Weber
Abstract: The present invention relates to a chamfered silicon carbide substrate which is essentially monocrystalline, and to a corresponding method of chamfering a silicon carbide substrate. A silicon carbide substrate according to the invention comprises a main surface (102), wherein an orientation of said main surface (102) is such that a normal vector ({right arrow over (O)}) of the main surface (102) includes a tilt angle with a normal vector ({right arrow over (N)}) of a basal lattice plane (106) of the substrate, and a chamfered peripheral region (110), wherein a surface of the chamfered peripheral region includes a bevel angle with said main surface, wherein said bevel angle is chosen so that, in more than 75% of the peripheral region, normal vectors ({right arrow over (F)}_i) of the chamfered peripheral region (110) differ from the normal vector of the basal lattice plane by less than a difference between the normal vector of the main surface and the normal vector of the basal lattice plane of the substrate.
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公开(公告)号：US12195878B2
公开(公告)日：2025-01-14
申请号：US17380690
申请日：2021-07-20
Applicant: SiCrystal GmbH
Inventor： Michael Vogel , Erwin Schmitt , Arnd-Dietrich Weber , Ralph-Uwe Barz , Dominik Bannspach
Abstract: The present invention provides monocrystalline 4H—SiC semi-finished products having a specific orientation of its crystal structure which is set such as to reduce or even eliminate the occurrence of cracks or fissures during mechanical processing, and method of producing same. The monocrystalline 4H—SiC semi-finished product, which has a longitudinal axis and an at least partially curved lateral surface parallel to said longitudinal axis, is characterized in that the crystal structure of the 4H—SiC semi-finished product is oriented with respect to the longitudinal axis such that at each position on the lateral surface of the semi-finished product there is a line segment which is intersected by at least a predetermined minimum number of parallel cleavage planes of the {1010} form per unit length, wherein the line segment is defined by a plane tangent to the lateral surface at said position.
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4.发明公开
公开(公告)号：US20240318352A1
公开(公告)日：2024-09-26
申请号：US18598090
申请日：2024-03-07
Applicant: SiCrystal GmbH
Inventor： Bernhard Ecker , Maximilian Kowasch , Ralf Müller , Philipp Schuh , Matthias Stockmeier , Daisuke Takegawa , Michael Vogel , Arnd-Dietrich Weber
CPC classification number: C30B33/02 , C30B29/36 , F27B17/0016 , F27D5/0037
Abstract: Thermal post-treatment of a silicon carbide (SiC) volume monocrystal which has a substantially cylindrical basic shape with a crystal length in an axial direction, a crystal diameter in a radial direction, a crystal central longitudinal axis extending in the axial direction, and with three boundary surfaces, namely, a bottom surface, a top surface and a circumferential edge surface. The SiC volume monocrystal is brought to a post-treatment temperature in order to reduce mechanical stresses present in the SiC volume monocrystal after completion of the previous growth, wherein an inhomogeneous temperature profile with a radial thermal gradient is set in the SiC volume monocrystal, which rises continuously from the crystal central longitudinal axis to the circumferential edge surface, and a heat exchange of the SiC volume monocrystal with a surrounding free space takes place via free heat radiation on at least two of the three boundary surfaces.
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公开(公告)号：US11236438B2
公开(公告)日：2022-02-01
申请号：US16492044
申请日：2018-03-07
Applicant: SICRYSTAL GMBH
Inventor： Michael Vogel , Bernhard Ecker , Ralf Müller , Matthias Stockmeier , Arnd-Dietrich Weber
Abstract: The present invention relates to a silicon carbide (SiC) substrate with improved mechanical and electrical characteristics. Furthermore, the invention relates to a method for producing a bulk SiC crystal in a physical vapor transport growth system. The silicon carbide substrate comprises an inner region (102) which constitutes at least 30% of a total surface area of said substrate (100), a ring shaped peripheral region (104) radially surrounding the inner region (102), wherein a mean concentration of a dopant in the inner region (102) differs by at maximum 5·1018 cm−3, preferably 1·1018 cm−3, from the mean concentration of this dopant in the peripheral region (104).
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公开(公告)号：US11781245B2
公开(公告)日：2023-10-10
申请号：US17544868
申请日：2021-12-07
Applicant: SICRYSTAL GMBH
Inventor： Michael Vogel , Bernhard Ecker , Ralf Müller , Matthias Stockmeier , Arnd-Dietrich Weber
Abstract: The present invention relates to a silicon carbide (SiC) substrate with improved mechanical and electrical characteristics. Furthermore, the invention relates to a method for producing a bulk SiC crystal in a physical vapor transport growth system. The silicon carbide substrate comprises an inner region (102) which constitutes at least 30% of a total surface area of said substrate (100), a ring shaped peripheral region (104) radially surrounding the inner region (102), wherein a mean concentration of a dopant in the inner region (102) differs by at maximum 5·1018 cm−3, preferably 1·1018 cm−3, from the mean concentration of this dopant in the peripheral region (104).
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公开(公告)号：US20220025546A1
公开(公告)日：2022-01-27
申请号：US17380690
申请日：2021-07-20
Applicant: SiCrystal GmbH
Inventor： Michael Vogel , Erwin Schmitt , Arnd-Dietrich Weber , Ralph-Uwe Barz , Dominik Bannspach
Abstract: The present invention provides monocrystalline 4H—SiC semi-finished products having a specific orientation of its crystal structure which is set such as to reduce or even eliminate the occurrence of cracks or fissures during mechanical processing, and method of producing same. The monocrystalline 4H—SiC semi-finished product, which has a longitudinal axis and an at least partially curved lateral surface parallel to said longitudinal axis, is characterized in that the crystal structure of the 4H—SiC semi-finished product is oriented with respect to the longitudinal axis such that at each position on the lateral surface of the semi-finished product there is a line segment which is intersected by at least a predetermined minimum number of parallel cleavage planes of the {1010} form per unit length, wherein the line segment is defined by a plane tangent to the lateral surface at said position.
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公开(公告)号：US20220025545A1
公开(公告)日：2022-01-27
申请号：US17380607
申请日：2021-07-20
Applicant: SiCrystal GmbH
Inventor： Michael Vogel , Erwin Schmitt , Arnd-Dietrich Weber , Ralph-Uwe Barz , Dominik Bannspach
Abstract: The present invention provides monocrystalline 4H—SiC substrates having a specific orientation of its crystal structure which is set such as to reduce or even eliminate the occurrence of cracks or fissures during mechanical processing, and method of producing same. The monocrystalline 4H—SiC substrate, which has a longitudinal axis and an at least partially curved lateral surface parallel to said longitudinal axis, is characterized in that the crystal structure of the 4H—SiC substrate is oriented with respect to the longitudinal axis such that at each position on the lateral surface of the semi-finished product there is a line segment which is intersected by at least a predetermined minimum number of parallel cleavage planes of the {1010} form per unit length, wherein the line segment is defined by a plane tangent to the lateral surface at said position.
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9.发明公开
公开(公告)号：US20240003054A1
公开(公告)日：2024-01-04
申请号：US18466188
申请日：2023-09-13
Applicant: SiCrystal GmbH
Inventor： Bernhard Ecker , Ralf Müller , Matthias Stockmeier , Michael Vogel , Arnd-Dietrich Weber
CPC classification number: C30B29/36 , C30B23/025 , C30B23/066 , C30B23/002 , C30B23/063
Abstract: An SiC volume monocrystal is processed by sublimation growth. An SiC seed crystal is placed in a crystal growth region of a growing crucible and SiC source material is introduced into an SiC storage region. During growth, at a growth temperature of up to 2,400° C. and a growth pressure between 0.1 mbar and 100 mbar, an SiC growth gas phase is generated by sublimation of the SiC source material and by transport of the sublimated gaseous components into the crystal growth region, where an SiC volume monocrystal grows by deposition from the SiC growth gas phase on the SiC seed crystal. A mechanical stress is introduced into the SiC seed crystal at room temperature prior to the start of the growth to cause seed screw dislocations present in the SiC seed crystal to undergo a dislocation movement so that seed screw dislocations recombine.
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10.发明公开
公开(公告)号：US20230416939A1
公开(公告)日：2023-12-28
申请号：US18466184
申请日：2023-09-13
Applicant: SiCrystal GmbH
Inventor： Bernhard Ecker , Ralf Müller , Matthias Stockmeier , Michael Vogel , Arnd-Dietrich Weber
IPC: C30B23/02 , C30B29/36 , C01B32/956
CPC classification number: C30B23/025 , C30B29/36 , C01B32/956
Abstract: A SiC volume monocrystal is produced by sublimation growth. An SiC seed crystal is placed in a crystal growth region of a growing crucible and SiC source material is introduced into an SiC storage region. During growth, at a growth temperature of up to 2,400° C. and a growth pressure between 0.1 mbar and 100 mbar, an SiC growth gas phase is generated by sublimation of the SiC source material and by transport of the sublimated gaseous components into the crystal growth region, where an SiC volume monocrystal grows by deposition from the SiC growth gas phase on the SiC seed crystal. Prior to the start of growth, the SiC seed crystal is examined at the growth surface for the presence of seed screw dislocations, nucleation centers are generated, wherein the nucleation centers are starting points for at least one compensation screw dislocation during the growth carried out subsequently.
