US5279701A
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Method for the growth of silicon carbide single crystals
Assignee: Sharp Corp
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Filing: 1992-08-24
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Granted: 1994-01-18
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Expires: 2012-08-24
Abstract
Abstract A method for the growth of silicon carbide single crystals is disclosed which includes the step of growing silicon carbide single crystals on a silicon single-crystal substrate. The silicon single-crystal substrate has growth areas with a crystal orientation inclined by an angle θ from the [100] direction toward at least one of the [011] and [011] directions and with a lateral dimension d taken along the direction of such inclination toward the [011] or [011] direction. The angle θ is set to be in the range of zero to tan -1 (√2/8) degrees (with the proviso that the angle θ is not equal to tan -1 (√2/2) degrees). The lateral dimension d is set to be in the range of 0.1 to 100 μm. In this method, the silicon carbide single crystals are grown to a thickness t approximately equal to or greater than (√2+tanθ)d/|1-√2tanθ|, so that these silicon carbide single crystals are substantially free of defects such as stacking faults.
Inventors
- 👤 Mitsuhiro Shigeta
- 👤 Akira Suzuki
- 👤 Katsuki Furukawa
- 👤 Yoshihisa Fujii
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:41
CPC Classifications
C; C30; C30B; C30B25/00; C30B25/02; C30B25/18; C30B29/00; C30B29/10; C30B29/36; Y; Y10; Y10S; Y10S148/00; Y10S148/148; Y10S438/00; Y10S438/931; Y10S438/973
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
248 words
A method for the growth of silicon carbide single crystals, said method comprising the preparation of a silicon single crystal substrate having growth areas and the step of growing silicon carbide single crystals on the growth areas with a thickness approximately equal to a more than critical thickness t, said growth areas having a crystal orientation inclined by an off angle θ from the [100] direction toward the [011] or [011] direction and said off angle θ being smaller than 10° (ten degrees) (with the proviso that the angle θ is not equal to tan (√2/2) degrees), said critical thickness t being approximately equal to d(√2+tanθ)/|1-√2tanθ| for said off angle θ and a lateral dimension d, said lateral dimension d being specified by rectangular coordinates attached onto said growth area, the two axes of said rectangular coordinates being taken parallel and perpendicular to [011] in case of an off angle θ toward [011], or the two axes of said rectangular coordinates being taken parallel and perpendicular to [011] in case of an off angle θ toward [011], said lateral dimension d being equal to the length of said growth area along said axis perpendicular to [011] in case of an off angle θ toward [011], or said lateral dimension d being equal to the length of said growth area along said axis perpendicular to [011] in case of an off angle θ toward [011], and said lateral dimension d being in the range of 0.1 to 100 μm.
Claim 2
Independent Claim
248 words
A method for the growth of silicon carbide single crystals, said method comprising the preparation of a silicon single crystal substrate having growth areas and the step of growing silicon carbide single crystals on the growth areas with a thickness approximately equal to a more than critical thickness t, said growth areas having a crystal orientation inclined by an off angle θ from the [100] direction toward the [011] or [011] direction and said off angle θ being smaller than 10° (ten degrees) (with the proviso that the angle θ is not equal to tan (√2/2) degrees), said critical thickness t being approximately equal to d(√2+tanθ)/|1-√2tanθ| for said off angle θ and a lateral dimension d, said lateral dimension d being specified by rectangular coordinates attached onto said growth area, the two axes of said rectangular coordinates being taken parallel and perpendicular to [011] in case of an off angle θ toward [011], or the two axes of said rectangular coordinates being taken parallel and perpendicular to [011] in case of an off angle θ toward [011], said lateral dimension d being equal to the length of said growth area along said axis perpendicular to [011] in case of an off angle θ toward [011], or said lateral dimension d being equal to the length of said growth area along said axis perpendicular to [011] in case of an off angle θ toward [011], and said lateral dimension d being in the range of 0.1 to 100 μm.
Claim 3
Dependent Claim
61 words
A method for the growth of silicon carbide single crystals according to claim 1, wherein said off angle θ is equal to tan -1 (√2/n) from the [100] direction toward the [011] direction, said critical thickness t being approximately equal to √2d(n+1)/|n-2| (where n is an integer of from 1 to 8, with proviso that it is not equal to 2).
Claim 4
Independent Claim
135 words
A method for the growth of silicon carbide single crystals, said method comprising the preparation of a silicon single crystal substrate having growth areas and the step of growing silicon carbide single crystals on the growth areas with a thickness approximately equal to or more than a critical thickness t, said growth areas having a crystal orientation of [100], said critical thickness t being approximately equal to √2d for a lateral dimension d, said lateral dimension d being specified by rectangular coordinates attached onto said growth area, the two axes of said rectangular coordinates being taken parallel to [011] and [011], said lateral dimension d being equal to the longer one of the length of said growth area along said axes, and said lateral dimension d being in the range of 0.1 to 100 μm.
Claim 5
Independent Claim
135 words
A method for the growth of silicon carbide single crystals, said method comprising the preparation of a silicon single crystal substrate having growth areas and the step of growing silicon carbide single crystals on the growth areas with a thickness approximately equal to or more than a critical thickness t, said growth areas having a crystal orientation of [100], said critical thickness t being approximately equal to √2d for a lateral dimension d, said lateral dimension d being specified by rectangular coordinates attached onto said growth area, the two axes of said rectangular coordinates being taken parallel to [011] and [011], said lateral dimension d being equal to the longer one of the length of said growth area along said axes, and said lateral dimension d being in the range of 0.1 to 100 μm.
Claim 6
Independent Claim
263 words
A method for the growth of silicon carbide single crystals, said method comprising the preparation of a silicon single crystal substrate having growth areas and the step of growing silicon carbide single crystals on the growth areas with a thickness approximately equal to or more than a critical thickness t, said growth areas having a crystal orientation inclined by an off angle θ from the [100] direction toward the [011] or [011] direction and said off angle θ being smaller than 10° (ten degrees) (with the proviso that the angle θ is not equal to tan (√2/2) degrees), said critical thickness t being approximately equal to d(√2+tanθ)/|1-√2tanθ| for said off angle θ and a lateral dimension d, said lateral dimension d being specified by rectangular coordinates attached onto said growth area, the two axes of said rectangular coordinates being taken parallel and perpendicular to [011] in case of an off angle θ toward [011], or the two axes of said rectangular coordinates being taken parallel and perpendicular to [011] in case of an off angle θ toward [011], said lateral dimension d being equal to the length of said silicon carbide single crystal grown on said growth area along said axes perpendicular to [011] in case of an off angle θ toward [011], or said lateral dimension d being equal to the length of said silicon carbide single crystal grown on said growth area along said axis perpendicular to [011] in case of an off angle θ toward [011], and said lateral dimension d being in the range of 0.1 to 100 μm.
Claim 7
Independent Claim
263 words
A method for the growth of silicon carbide single crystals, said method comprising the preparation of a silicon single crystal substrate having growth areas and the step of growing silicon carbide single crystals on the growth areas with a thickness approximately equal to or more than a critical thickness t, said growth areas having a crystal orientation inclined by an off angle θ from the [100] direction toward the [011] or [011] direction and said off angle θ being smaller than 10° (ten degrees) (with the proviso that the angle θ is not equal to tan (√2/2) degrees), said critical thickness t being approximately equal to d(√2+tanθ)/|1-√2tanθ| for said off angle θ and a lateral dimension d, said lateral dimension d being specified by rectangular coordinates attached onto said growth area, the two axes of said rectangular coordinates being taken parallel and perpendicular to [011] in case of an off angle θ toward [011], or the two axes of said rectangular coordinates being taken parallel and perpendicular to [011] in case of an off angle θ toward [011], said lateral dimension d being equal to the length of said silicon carbide single crystal grown on said growth area along said axes perpendicular to [011] in case of an off angle θ toward [011], or said lateral dimension d being equal to the length of said silicon carbide single crystal grown on said growth area along said axis perpendicular to [011] in case of an off angle θ toward [011], and said lateral dimension d being in the range of 0.1 to 100 μm.
Claim 8
Independent Claim
142 words
A method for the growth of silicon carbide single crystals, said method comprising the preparation of a silicon single crystal substrate having growth areas and the step of growing silicon carbide single crystals on the growth areas with a thickness approximately equal to or more than a critical thickness t, said growth areas having a crystal orientation of [100], said critical thickness t being approximately equal to √2d for a lateral dimension d, said lateral dimension d being specified by rectangular coordinates attached onto said growth area, the two axes of said rectangular coordinates being taken parallel to [011] and [011], said lateral dimension d being equal to the longer one of the length of said silicon carbide single crystal grown on said growth area along said axes, and said lateral dimension d being in the range of 0.1 to 100 μm.
Claim 9
Independent Claim
142 words
A method for the growth of silicon carbide single crystals, said method comprising the preparation of a silicon single crystal substrate having growth areas and the step of growing silicon carbide single crystals on the growth areas with a thickness approximately equal to or more than a critical thickness t, said growth areas having a crystal orientation of [100], said critical thickness t being approximately equal to √2d for a lateral dimension d, said lateral dimension d being specified by rectangular coordinates attached onto said growth area, the two axes of said rectangular coordinates being taken parallel to [011] and [011], said lateral dimension d being equal to the longer one of the length of said silicon carbide single crystal grown on said growth area along said axes, and said lateral dimension d being in the range of 0.1 to 100 μm.
Claim 10
Dependent Claim
61 words
A method for the growth of silicon carbide single crystals according to claim 4, wherein said off angle θ is equal to tan -1 (√2/n) from the [100] direction toward the [011] direction, said critical thickness t being approximately equal to √2d(n+1)/|n-2| (where n is an integer of from 1 to 8, with proviso that it is not equal to 2).
Claim 11
Dependent Claim
20 words
A method for the growth of silicon carbide single crystals according to claim 6, wherein n is equal to 6.
Claim 12
Dependent Claim
20 words
A method for the growth of silicon carbide single crystals according to claim 2, wherein n is equal to 6.
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